Holder for pipe in heat exchanger, method and device for manufacturing heat exchanger using said holder, and air conditioner and/or outdoor unit having said heat exchanger

ABSTRACT

The current invention provides a tube-grasping body for grasping an insert tube in a heat exchanger, and heat exchanger production methods and apparatuses utilizing the tube-grasping body, wherein the tube-grasping body enables to enlarge and connect an insert tube to a heat radiating fin for producing a heat exchanger, still keeping the total length of insert tubes at an almost same level even after the enlargement; and the tube-grasping body is connected at its exterior to the guide-pipe.

FIELD OF THE INVENTION

The current invention relates to a tube-grasping body for grasping an insert tube in a heat exchanger, heat exchanger production methods and apparatuses utilizing the tube-grasping body, and an air conditioner and/or an outdoor unit equipped with the heat exchanger produced by the methods and apparatuses.

BACKGROUND OF THE INVENTION

Japanese patent No. 63-188433 (hereinafter referred to as ‘the Invention A’) and No. 10-85878 (applied by the applicant of the current patent application, and hereinafter referred to as ‘the Invention B’) are examples of the prior arts, which keep the entire length of insert tubes being enlarged, at an almost same level, even after the enlargement.

That is, as shown in FIG. 12( a), as a method of fixing a hairpin tube 7 at a heat radiating fin by inserting a tube-enlarging mandrel 2 into the opening 7 b of said hairpin tube 7 in a heat exchanger 5, in a configuration where multiple hairpin tubes 7 are inserted into multiple heat radiating fins 6 which are overlaid and separated by a prescribed space isolation, ‘the Invention A’ provides a method wherein the hairpin part 7 c of said hairpin tube 7 is fixed by a hook body 10 which is not movable toward said opening 7 b; then the tube 7 is enlarged at the side of the opening 7 b, rather than the side of the heat radiating fin 6, by inserting the tube-enlarging mandrel 2 from the opening 7 b of the tube 7, and then the enlargement portion 7 d is fixed in the through hole 9 of the clamp 8 which is not movable toward the said hairpin part 7 c; then, the tube-enlarging mandrel 2 is inserted into the hairpin tube 7, in the state where the hairpin tube 7 is fixed by the clamp not to move toward the hairpin part 7 and the hairpin tube 7 is fixed by the hook body 10 not to move toward the opening 7 b.

According to the method above, after the side of the opening 7 b of the hairpin tube 7, rather than the side of the heat radiating fin 6, is fixed in the through hole 9 of the clamp 8 at the side of the opening 7 b not to move toward the hairpin part 7 c, the hairpin tube 7 tends to shrink during the enlargement process of inserting the tube-enlarging mandrel 2. However, since the hairpin part 7 c is also fixed by the hook body 10, shrinkage of the hairpin tube 7 is prevented and absorbed by reducing the thickness in the hairpin tube 7. As a result, shrinkage in the entire length of tubes is kept at a minimum even after the enlargement.

However, the heat exchanger production method explained above has problems as detailed below.

That is, in the method above, as shown in FIG. 12( b), since the opening 7 b of the hairpin tube 7 is fixed in the through hole 9 of the clamp 8, if hairpin tubes are inserted in a zigzag pattern in multiple columns such as columns of 3, 4, or etc., there exists a problem that hairpin tubes 7 sitting at the interior side in the heat exchanger cannot be fixed by the clamp 8.

On the other hand, as shown in (c) in the same figure, the problem above can be resolved, by mechanically varying the diameter of the through hole 9 of the clamp 8, by an aperture-like tool operating like an aperture in a camera. However, if the space between each of hairpin tubes 7 is fully taken up with complex components, or if said space is smaller than the gap between said aperture-like tools, there exists a space problem for setting up said aperture-like tools, and thus the limiting factor stated above still develops.

Also, if the diameter of the hairpin tube being enlarged in the heat exchanger 5 is changed according to the spec of the heat exchanger 5, the through holes 9 of the clamp 8 can no longer firmly fix the side of the opening 7 b of the hairpin tube 7. Also, other various similar problems develop.

Thus, to resolve all of the problems stated above, the applicant of this application applied ‘the Invention B’ for the patent registration. According to ‘the invention B’, as shown in FIG. 1, in a heat exchanger production apparatus 1 configured with the main body 1 a installed on the base platform 1 b, 1 c is the component-loading platform of the heat exchanger 5, which is vertically installed on said base platform 1 b. Inside said heat exchanger 5, a plurality of hairpin tubes 7 with prescribed lengths are inserted in a row (not shown in the figure) into multiple heat radiating fins 6 along the surface of the component-loading platform 1 c. Also, above said component-loading platform 1 c, a pressing-plate 11 is installed to elevate in order to press and fix said heat exchanger 5 between the component-loading platform 1 c and the pressing-plate 11.

2 represents the tube-enlarging mandrel which is installed for moving back and forth on said main body 1 a, keeping its horizontal status. As shown in FIGS. 2( a) and (b), the tube-enlarging mandrel 2 is connected from its exterior to the tube-grasping body 3 to enable to move the tube-grasping body along the tube-enlarging mandrel 2. Said tube-grasping body 3 is equipped with a plurality of tube-contacting parts 3 f on which the slopes 3 b are formed and slanted in the widening direction, toward the side of the opening 7 b of the corresponding tube 7, and which are capable of radially expanding or axially compressing (the arrow E) in the cross direction of the longitudinal length of said hairpin tube 7. Said slope 3 b is formed to reach the end-line 3 o of the tube-contacting part 3 f. Said tube-grasping body 3 is screwed and connected to the tube-grasping body holder 3 l by the bolt 3 k formed at the other side, the opposite side of said tube-contacting parts 3 f. Said tube-grasping body holder 3 l is capable of moving back and forth (the arrow F) by a sliding means such as a cylinder (not shown in the figure), in the longitudinal direction of the hairpin tube 7, within a prescribed pitch. Also, the guide-pipe 3 c is screwed and connected to the guide-pipe holder 3 d by the bolt 3 h formed at the other side. Said guide-pipe holder 3 d is capable of moving back and forth (the arrow G) by a sliding means such as a cylinder (not shown in the figure).

Four of said tube-contacting parts 3 f of the tube-grasping body 3 are formed in the longitudinal direction of said tube-enlarging mandrel 2 to enclose the exterior circumferential surface of said tube-enlarging mandrel 2 (for example, if 6 is proper for a specific exterior diameter of the tube, then 6 or other number is set). Also, between the tube-contacting parts 3 f, slits, each of which has a uniform length and a uniform separation width of a prescribed width 3 u, are formed at four places (the quantity of such slits does not have to be 4 and is properly determined in proportion to the count of tube-contacting parts 3 f). Through said slits, the diameter of each of the tube-contacting parts 3 f is decreased in the axial direction of the tube-enlarging mandrel 2, as the guide-pipe 3 c is advanced, by the guide-pipe holder 3 d, toward the heat exchanger, in order to press and slide along the slope 3 b which has been formed on the exterior surface of each of said tube-contacting parts 3 f, and which is slanted in the widening direction toward the opening 7 b of the corresponding tube 7. It is structured by a so-called collect chuck. The tube-grasping bodies 3 in their multitudes (not shown in the figure) with said plural tube-contacting parts 3 f are installed along the surface of said component-loading platform 1 c, in order to be faced with each of the opening 7 b of hairpin tubes 7 being inserted into the heat exchanger 5.

4 is an enclosing-body shifting device comprising: a pair of enclosing-bodies 4 a which is installed on said base platform 1 b, and which is supported to rotate to enclose the hairpin part 7 c of the hairpin tube 7 being inserted into the heat radiating fin 6 of said heat exchanger 5; a driving-cylinder 4 e to drive to open or close said enclosing-body 4 a; a base plane 4 d with said driving-cylinder 4 e and a pair of enclosing-bodies 4 a; a guide rail 12 to slide said base plane 4 d, to or from said component-loading 1 c; and a round-trip cylinder 4 f which enables said base plane 4 d to move back and forth. Multiple quantity (not shown in the figure) of said pair of enclosing-bodies 4 a are installed along the plane of said component-loading platform 1 c, to be faced with each of the hairpin part 7 c of hairpin tubes 7 which are inserted into the heat radiating fin 6 of the heat exchanger 5.

Explanation is given below about production of a heat exchanger 5, wherein a heat exchanger production apparatus 1 utilizes the tube-grasping body 3 configured as above, and the tube-enlarging mandrel 2 is inserted into the hairpin tube 7. First, as shown in FIG. 1, the heat exchanger 5 is installed on said component-loading platform 1 c, and, subsequently, said heat exchanger 5 is pressed and fixed between the component-loading platform 1 c and the pressing-plate 11, by lowering the pressing-plate 11 located above.

Next, the base plane 4 d is advanced (not shown in the figure) along the guide rail 12, by operating the round-trip cylinder 4 f of the enclosing-body shifting device 4. At the same time, the driving-cylinder 4 e is operated, in order to enclose the hairpin part 7 c of each of hairpin tubes 7, as indicated in FIG. 11, by the tongue shaped concavity 4 g which resembles a tongue when viewed from the plane of a pair of enclosing-bodies 4 a. Corresponding to said tongue shaped concavity 4 g, a tongue shaped convexity 4 c, which resembles a tongue when viewed from said plane, is formed on the interior surface of said tongue shaped concavity 4 g. Said tongue shaped convexity 4 c turns around the U-shaped interior circumferential surface of said hairpin part 7 c in order to firmly stop the shrinkage of the hairpin tube 7 during the enlarging process.

Next, from the opening 7 b of each of said hairpin tubes 7, as shown in FIG. 2( c), by inserting (the arrow A) each of the tube-enlarging mandrels 2 by a prescribed depth, the enlargement portion 7 d with a prescribed length is formed. Subsequently, by advancing (the arrow B) the tube-grasping body 3, by the tube-grasping body holder 3 l, from the opening 7 b of the hairpin tube 7, toward the circumferential surface 7 e of said enlargement portion 7 d, the tube-grasping body 3 becomes connected to the exterior of said circumferential surface 7 e, in the state where said circumferential surface 7 e is surrounded by the tube-contacting parts 3 f.

Afterwards, if the guide-pipe 3 c is moved (the arrow C), by the guide-pipe holder 3 d, in the same direction of the movement of the tube-enlarging mandrel 2, the guide-pipe 3 c presses the slope 3 b while sliding along the same slope which has been formed on the exterior surface of each of said tube-contacting parts 3 f, and which is slanted in the widening direction toward the opening 7 b of the corresponding tube 7. Thus, the diameter of the tube-contacting parts 3 f is reduced in the axial direction of the tube-enlarging mandrel 2, through the space isolation of the prescribed width 3 u of the slits 3 a. As a result, each of said tube-contacting parts 3 f becomes to firmly grasp and support the circumferential surface 7 e of the enlargement portion 7 d of the hairpin tube 7.

Next, from this state, by moving said tube-enlarging mandrel 2 toward the hairpin part 7 c of the hairpin tube 7, in order to support both of the hairpin part 7 c and the opening 7 b of the hairpin tube 7, it is possible to produce a heat exchanger, still keeping shrinkage of the entire length of hairpin tubes 7 at a minimum.

Also, when the tube-enlarging mandrel 2 is advanced toward the hairpin part 7 c of the hairpin tube 7 while the circumferential surface 7 e of the enlargement portion 7 d is firmly grasped, as explained above, by plural tube-contacting parts 3 f of the tube-grasping body 3, at the side of the opening 7 b of the hairpin tube 7; the enclosing-body shifting device 4, equipped with the enclosing-bodies 4 a capable of enclosing said hairpin part 7 c, is moved back little (not shown in the figure) in the same direction of the movement of the tube-enlarging mandrel 2, in order to give some tensile strength for the entire hairpin tube 7. Thus, It is possible to produce a heat exchanger, keeping the shrinkage of the entire length of the hairpin tube 7 at a minimum, and considering the problem of shrinking of the entire length of the hairpin tube 7 during the enlarging process, as well as the problem of escaping of the hairpin tube 7 from the tube-contacting parts 3 f and the enclosing-body 4 a. As a result, it is possible to produce a heat exchanger, still keeping the material cost at a minimum.

Thus, it is possible to firmly grasp, by each of the tube-grasping bodies 3 having plural tube-contacting parts 3 f, each of hairpin tubes 7 sitting at the interior side in the heat exchanger, as well as each of the tubes sitting at the exterior side in the heat exchanger, even for the following example cases: the case where hairpin tubes 7 are inserted into the heat radiating fin 6 of a heat exchanger 5 in a zigzag pattern (not shown in the figure); and the case where hairpin tubes 7 are inserted in a zigzag pattern, in multiple columns such as columns of 3, 4, or etc. (not shown in the figure) to decrease the gap (the insert pitch) between each of hairpin tubes 7.

Thus, since the tube-contacting parts 3 f of said tube-grasping body 3 grasp the circumferential surface 7 e of the enlargement portion 7 d of the hairpin tube 7, by decreasing the diameter of the tube-contacting parts 3 f in the axial direction, through the slits which are of a prescribed width 3 u, and which are formed between each of the tube-contacting parts 3 f, even for the case where the diameter of the hairpin tube 7 being enlarged is different according to the spec of the heat exchanger; it is possible to firmly and surely grasp the side of the opening 7 b of the hairpin tube 7, by adjusting through the space distance of the slits 3 a of a prescribed width 3 u, between each of the tube-contacting parts 3 f, even if there is little difference in each of diameters of the tubes. Also, as for the hairpin part 7 c, since there is no need to replace the hook body 10 with another hook body having an almost identical circular arc to the interior circumference of the hairpin part 7 c, in order to adapt to the different hairpin part 7 c of hairpin tubes 7 with different diameters; and since it is possible to firmly and surely grasp by a pair of enclosing-bodies 4 a, without altering the circular arc of the hairpin part 7 c of the hairpin tube 7; it is possible to produce a heat exchanger, performing the enlarging process desired, without altering the heat exchanger production apparatus, even for the following cases: the case where the exterior diameter (the diameter of the tube, measured considering the circular arc) of the hairpin tube 7 being enlarged is different according to the spec of the heat exchanger 5, and the case where the entire length of hairpin tubes 7 is somewhat different.

Also, relating to the case where the hairpin part 7 c of the hairpin tube 7 is firmly and surely enclosed by a pair of enclosing-bodies 4 a as shown above, it is possible to exchange a pair of enclosing-bodies 4 a to other type with a proper opening size, width, and length, according to the gap between insert tubes facing each other and the distance extruded from the terminal side of the heat radiating fin 6 of the hairpin part 7 c of the hairpin 7; even for any of the following example cases:

-   -   the case where hairpin tubes 7 are inserted into a heat         radiating fin 6 of a heat exchanger 5 in the same zigzag pattern         (not shown in the figure) as above, and     -   the case where hairpin tubes 7 are inserted in a zigzag pattern,         in multiple columns (not shown in the figure) such as columns of         3, 4, or etc. to decrease the gap between each of hairpin tubes         (the insert pitch).         However, unlike the hook body 10 of the prior art, since the         hairpin part is enclosed by a pair of enclosing-bodies 4 a,         there exists some permissible range and it is thus possible to         avoid frequent change of the hook body 10. However, the most         important point is the fact that it is possible to firmly fix         the hairpin part 7 c of each of the hairpin tubes 7 sitting at         the interior side in the heat exchanger, as well as the hairpin         part 7 c of each of the hairpin tubes sitting at the exterior         side in the heat exchanger, by allocating a pair of enclosing         bodies 4 a to each of the hairpin parts 7 c.

Also, even if insert tubes 7 of other types than the hairpin tube are inserted, for example, if multiple straight tubes (not shown in the figure) are inserted, it is possible to produce a high quality heat exchanger with high precision, by enclosing and supporting, by a pair of the enclosing-bodies 4 a, an end of the straight tube extruding from the terminal side of the heat radiating fin 6, and by inserting the tube-enlarging mandrel 2 into the opening 7 b of the other end of the straight tube, by the same procedure as shown above.

Therefore, even for the case where insert tubes are inserted into a heat radiating fin, in multiple columns such as columns of 3, 4, or etc. to decrease the gap between insert tubes, and the case where the diameter of insert tubes being enlarged is different according to the spec of the heat exchanger, it is possible to firmly grasp and perform the enlarging process for insert tubes sitting at the interior side in the heat exchanger, as well as the tubes sitting at the exterior side in the heat exchanger. As a result, it is possible to produce a high quality heat exchanger, still keeping the material cost at a minimum by maintaining shrinkage of total length of insert tubes at a minimum.

Also, as shown in FIG. 2( d), if a bump 3 e is formed at each of the tube-contacting parts 3 f for pressing (the arrow D) the circumferential surface 7 e of said enlargement portion 7 d, at the position where each of the tube-contacting parts meets the enlargement portion 7 d of the hairpin tube 7, in order to build up the extruded-part 7 g extruding from the interior circumferential surface 7 f of said hairpin 7, in the axial direction of the tube-enlarging mandrel 2; it is possible to surely set the reference location of the opening 7 b during the enlargement process, and therefore, it is possible to produce a high precision heat exchanger by the enlarging process with higher precision.

On the other hand, the method, which is very similar to the Japanese Patent 10-85878, and which still considers the situation explained in FIG. 2( d) above, is Japanese Patent 9-99334 (hereinafter referred to as ‘Patent Document 3’) wherein a slope is formed in front of the bump which is formed at each of the tube-contacting parts, in order to prevent said opening from being deformed by a collision with the opening; a slope is formed in front of the guide pipe, for reducing the sliding abrasion against the slope on the exterior surface of each of said tube-contacting parts; a bolt is formed on the exterior circumferential surface of the tube-contacting part, a nut is formed on the interior circumferential surface of the guide-pipe, and said guide-pipe is screwed by said bolt and nut and installed for moving said guide-pipe back and forth.

SUMMARY OF THE INVENTION

The current invention resolves the problems explained below.

-   That is, according to the heat exchanger production apparatus 1     configured as above, since the tube-enlarging mandrel 2 is connected     from its exterior to the tube-grasping body 3 to enable to move the     tube-grasping body along the tube-enlarging mandrel 2;     -   said tube-grasping body 3 is equipped with a plurality of         tube-contacting parts 3 f on which the slopes 3 b are formed and         slanted in the widening direction, toward the side of the         opening 7 b of the corresponding tube 7, and which are capable         of radially expanding or axially compressing (the arrow E) in         the cross direction of the longitudinal length of said hairpin         tube 7;     -   said slope 3 b is formed to reach the end-line 3 o of the         tube-contacting part 3 f;     -   said tube-grasping body 3 is screwed and connected to the         tube-grasping body holder 3 l by the bolt 3 k formed at the         other side, the opposite side of said tube-contacting parts 3 f.         Said tube-grasping body holder 3 l is capable of moving back and         forth (the arrow F) by a sliding means such as a cylinder (not         shown in the figure), in the longitudinal direction of the         hairpin tube 7, within a prescribed pitch; and     -   the guide-pipe 3 c is also screwed and connected to the         guide-pipe holder 3 d by the bolt 3 h formed at the other side.         Said guide-pipe holder 3 d is capable of moving back and forth         (the arrow G) by a sliding means such as a cylinder (not shown         in the figure);         by sliding said guide-pipe 3 c toward the opening 7 b of the         tube 7 along the slopes 3 b of the tube-contacting parts 3 f,         the diameter of the tube-contacting parts 3 f is reduced in the         axial direction. At the same time, the bump 3 e, which is formed         at the side of the opening 7 b on the interior surface of each         of the tube-contacting parts 3 f, presses the circumferential         surface 7 e of the enlargement portion 7 d of the hairpin tube         7, in order to form an extruded-part 7 g extruding in the axial         direction of the tube 7. Thus, the tube-contacting parts become         to firmly grasp and support the tube, and, therefore, it is         possible to accurately set the reference point of the opening 7         b, during the enlarging process, such that producing a high         precision heat exchanger is possible by the higher precision         enlarging process. However, since, in the tube-grasping body 3         configured as above, the slope 3 b of each of the         tube-contacting parts 3 f is formed to reach the end-line 3 o of         each of the tube-contacting parts 3 f, it is necessary to         advance said guide-pipe 3 c, while sliding along the slopes 3 b,         to the position where the end-line of the guide-pipe 3 c         contacts the end-line 3 o of the tube-contacting part 3 f.

Recently, there exists a trend of downsizing, not only the heat exchanger 5 itself (tubes being downsized and etc.), but also straight tubes or hairpin tubes 7 being inserted into the heat radiating fin 6 of said heat exchanger 5, due to the problems of saving in energy and cost. Therefore, it is needed to have a heat exchanger 5 with a smaller gap between each of tubes 7 than the prior arts, for the following example cases: the case where straight tubes or hairpin tubes 7 are inserted in a row (not shown in the figure) into the heat radiating fin 6 of the heat exchanger 5, the case where tubes 7 are inserted in a zigzag pattern (not shown in the figure), and the case where tubes 7 are inserted in multiple columns such as columns of 3, 4, or etc (not shown in the figure).

On the other hand, according to the heat exchanger production apparatus 1 configured as above, even if the diameter of the hairpin tube 7 of the heat exchanger 5 being enlarged is different according to the spec of the heat exchanger 5, since the circumferential surface 7 e of the enlargement portion 7 d of the hairpin tube 7 is grasped by each of the tube-contacting parts 3 f of the tube-grasping body 3, by adjusting, within some range, the space distance of a prescribed width 3 u of each of the slits 3 a which are formed between each of the tube-contacting parts; it is possible to firmly and surely grasp the side of the opening 7 b of the hairpin tube 7, by automatically adapting to the difference in tube diameter through the slits between each of the tube-contacting parts 3 f. However, unfortunately, according to the tube-grasping body 3 of the prior art, since the slope 3 b of each of the tube-contacting parts 3 f is formed to reach the end-line 3 o of each of the tube-contacting parts 3 f, it is necessary to advance the end-line of the guide-pipe 3 c to the end-line 3 o of the tube-contacting part 3 f, during shrinking of the diameter of the tube-contacting parts 3 f of the tube-grasping body 3. Thus, if both of exterior diameters of the tube-contacting parts 3 f and the tube-grasping body 3 are minimized, the exterior diameter of the guide-pipe 3 c being connected at the exterior of the tube-grasping body 3 is automatically determined as the reference diameter (the interior diameter itself when viewed from the guide-pipe 3 c), the exterior diameter measured between summits of the opposing slopes 3 b which are faced each other, and which are formed to reach the end-line 3 o of the corresponding tube-contacting parts whose diameter is being decreased during the enlargement. Thus, there is a problem in the exterior diameter of each of the guide-pipes 3 c, in order to allocate to each of straight tubes or hairpin tubes 7, when the gap between the tubes is significantly reduced. As a result, due the problem of contacting neighboring guide-pipes 3 c, there exists a problem of developing a limit in the gap (pitch) between each of the tube-grasping bodies 3, in allocating each of straight tubes or hairpin tubes 7 to a tube-grasping body 3 which is connected at its exterior to guide-pipe 3 c.

Also, according to PATENT DOCUMENT 3 of the prior arts, a bolt is formed on the exterior circumferential surface of the tube-contacting part, and a nut is formed on the interior circumferential surface of the guide-pipe, in order to join them together and move said guide-pipe back and forth. However, if the gap between each of straight tubes or hairpin tubes 7 being inserted into said heat radiating fin 6 is significantly reduced comparing to the prior arts, there exists the same problem as above, such a problem as a limit in the gap between each of the tube-grasping bodies 3, due to the problems such as the height of the threads of the bolt and nut or the gap (pitch) between screws. Thus, to resolve problems such as the cost and the configuration for any of cases above, it is requested the development of a tube-grasping body 3 or a heat exchanger production apparatus utilizing said tube-grasping body 3, wherein

-   -   said tube-grasping body 3 is simply configured to slide back and         forth, toward the opening 7 b, in order to radially expand or         axially compress said tube-contacting parts 3 f of the         tube-grasping body 3; and     -   said tube-grasping body 3 is able to significantly reduce the         gap (pitch), still avoiding the contact with neighboring         guide-pipes 3 c, even when the gap between each of straight         tubes or hairpin tubes 7 being inserted into the heat radiating         fin 6 is significantly reduced.

Also, not limiting to the case where the gap between each of straight tubes or hairpin tubes 7 being inserted into the heat radiating fin 6 is significantly reduced comparing to the prior arts, for example, if the exterior diameter of the enlargement portion of the tube is smaller than the interior diameter of the tube-grasping body 3 or the interior diameter between tube-contacting parts 3 f of said tube-grasping body 3, it is possible for the tube-grasping body 3 or the tube-contacting parts 3 f to grasp the exterior circumferential surface 7 e of the enlargement portion 7 d of each of straight tubes or hairpin tubes 7. However, if the exterior diameter of the enlargement portion 7 d of the tube 7 is about the same size as the interior diameter of the tube-grasping body 3 or the interior diameter between the tube-contacting parts 3 f of said tube-grasping body 3 (the interior diameter between the bumps 3 e if bumps 3 e are formed), or if the axis of said enlargement portion 7 d is away, by some degree, relative to the longitudinal direction of the tube-enlarging mandrel 2, from the axis of the tube-grasping body 3, there develops a case where the end-line 3 o of each of the tube-contacting parts 3 f contacts the opening 7 b of the tube such that at least one of them is damaged. Thus, an improvement is required.

The current invention provides a tube-grasping body for grasping an insert tube in a heat exchanger, heat exchanger production methods and apparatuses utilizing the tube-grasping body, and an air conditioner and/or an outdoor unit equipped with the heat exchanger produced by the methods and apparatuses; in order to produce a heat exchanger wherein the total length of the insert tubes is kept at an almost same level even after the enlargement, still satisfying the following requirements:

-   -   preventing one end from being transformed or deformed by         collision of the end-line of the tube-contacting parts of the         tube-grasping body, with the opening of the tube where the         enlargement portion is formed;     -   preventing a contact with neighboring guide-pipes, when         allocating a tube-grasping body being connected at its exterior         to the guide-pipe, to each of straight tubes or hairpin tubes;         and     -   firmly supporting the enlargement portion of each of the tubes         sitting at the interior side in the heat exchanger, as well as         that of each of the tubes sitting at the exterior side in the         heat exchanger, in the following heat exchangers:         -   a downsized heat exchanger where the gap (pitch) between             each of the tube-grasping bodies is minimized, and         -   a heat exchanger where the gap between each of the tubes is             significantly reduced;             to resolve all the problems occurring in the following             example cases:         -   the case where the gap between straight tubes or hairpin             tubes is decreased, due to downsized insert tubes due to             savings in energy or cost (use of downsized tubes or             downsized heat exchanger itself);         -   the case where the gap between insert tubes is decreased due             to insertion of straight tubes or hairpin tubes into a heat             radiating fin in a zigzag pattern;         -   the case where the gap between insert tubes is decreased to             enable them to be inserted into a heat radiating fin in             multiple columns such as columns of 3, 4, or etc.;         -   the case where the diameters of insert tubes being enlarged             are different according to the spec of the heat exchanger;         -   the case where the gap between each of straight tubes or             hairpin tubes being inserted into said heat radiating fin is             significantly decreased comparing to the prior arts;         -   the case where the exterior diameter of the enlargement             portion of the insert tube becomes about the same size as             the interior diameter of the tube-grasping body itself or             the interior diameter between the tube-contacting parts (the             interior diameter between the bumps if bumps are formed on             the interior surface of the tube-contacting parts); and         -   the case where the axis of said enlargement portion is away,             by some degree, relative to the direction of the             longitudinal length of the tube-enlarging mandrel, from the             axis of the tube-grasping body.

The present invention provides the ways to resolve the problems explained above. That is, the invention in claim 1 is to provide a tube-grasping body for grasping an insert tube in a heat exchanger,

-   -   which is used in a heat exchanger production apparatus 1;     -   which is also connectable at the exterior of a tube-enlarging         mandrel 2, for moving back and forth, along said tube-enlarging         mandrel 2 which is penetrable from the opening 7 b of a tube 7         inserted into a heat radiating fin 6 of a heat exchanger 5;     -   which is also equipped with a plurality of tube-contacting parts         3 f, capable of radially expanding or axially compressing in the         cross direction of the longitudinal length of said tube 7;     -   which is also equipped with slopes 3 b slanting gradually in the         widening direction toward the opening 7 b of the corresponding         tube, wherein each of the slopes 3 b is formed on the exterior         surface of each of said tube-contacting parts 3 f;     -   which also radially expands or axially compresses each of said         tube-contacting parts 3 f, by a sliding means which moves back         and forth in the longitudinal direction of the tube, along said         slopes 3 b of the tube-contacting parts 3 f; and which is also         characterized by the configuration wherein         -   said tube-contacting parts 3 f, capable of radially             expanding or axially compressing, are formed and separated             by a plurality of slits 3 a which are of prescribed widths 3             u, and which are formed in the longitudinal direction of the             tube-grasping body 3, the same direction of the movement of             the tube-enlarging mandrel 2; and         -   the width of each of said slits 3 a is gradually increased             from said prescribed width 3 u to an expanded width 3 x,             from a prescribed location toward the opening 7 b of said             tube 7.

The invention in claim 2 is to provide the tube-grasping body for grasping an insert tube in a heat exchanger, wherein

-   -   a sliding means is provided by the guide-pipe 3 c, which moves         back and forth in the longitudinal direction of the tube, along         said slopes 3 b of the tube-contacting parts 3 f; and     -   the maximum exterior diameter 3 v of said tube-grasping body 3         is set below the exterior diameter 3 w of the guide-pipe 3 c,         wherein the maximum exterior diameter 3 v is formed and         configured by the opposing tube-contacting parts 3 f facing each         other in order to build up said slopes 3 b.

The invention in claim 3 is to provide the tube-grasping body for grasping an insert tube in a heat exchanger, wherein

-   -   each of said tube-contacting parts 3 f, capable of radially         expanding or axially compressing, is bent to form a smooth curve         with or without a edge on the bent portion, in the radial         direction, from a prescribed location of each of said slits 3 a         toward the opening 7 b of the tube 7, in order to gradually         expand the width of each of said slits 3 a from the prescribed         width 3 u to the expanded width 3 x, from a prescribed location,         toward the opening 7 b of the tube 7.

The invention in claim 4 is to provide the tube-grasping body for grasping an insert tube in a heat exchanger, wherein

-   -   a bump 3 e is formed to extrude from the interior surface of         each of said tube-contacting parts 3 f, at the side of the         opening 7 b, in the axial direction of the tube 7; and     -   a slope 3 m, which has a straight or curved sloping side, is         formed at said bump 3 e, and slanted in the widening direction,         from the summit 3 p of the bump 3 e, toward the opening 7 b of         the tube 7 facing the end-line 3 o of the tube-contacting part 3         f, in order to prevent said opening 7 b from being deformed by         collision of the bump 3 e with the opening 7 b of the tube 7         when the opening 7 b of the tube 7 is connected at its exterior         to the tube-contacting parts 3 f.

The invention in claim 5 is to provide the tube-grasping body for grasping an insert tube in a heat exchanger, wherein

-   -   a limiting means is installed at said tube-grasping body 3         having tube-contacting parts 3 f when said tube-grasping body 3         is held by the tube-grasping body holder 3 l, in order to limit         the location of the radial expansion or the axial compression of         the tube-contacting parts 3 f of the tube-grasping body 3         (limiting rotation of the tube-grasping body holder 3 l).

The invention in claim 6 is to provide the tube-grasping body for grasping an insert tube in a heat exchanger, wherein

-   -   a slope 3 g, which has a straight or curved sloping side, is         formed on the interior circumference of said guide-pipe 3 c at         its end side, and slanted in the widening direction toward the         opening 7 b of the corresponding tube 7, in order to reduce the         sliding abrasion against each of the slopes 3 b formed on the         exterior surface of each of said tube-contacting parts 3 f; and     -   said slope 3 b is also formed, on the exterior surface of each         of the tube-contacting parts 3 f of said tube-grasping body 3,         at such a position that the slope 3 b is not allowed to reach         the end-line 3 o of each of said tube-contacting parts 3 f.

The invention in claim 7 is to provide a heat exchanger production method, utilizing a tube-grasping body for grasping an insert tube in a heat exchanger, the method comprising:

-   -   the first process wherein         -   an enlargement portion having a prescribed length is formed,             by inserting a tube-enlarging mandrel by a prescribed depth,             from the opening of an insert tube being inserted into a             heat radiating fin of a heat exchanger;     -   the second process wherein         -   the exterior of said enlargement portion is surrounded and             connected, by         -   the tube-grasping body wherein             -   said tube-contacting parts, capable of radially                 expanding or axially compressing, are formed and                 separated by a plurality of slits which are of                 prescribed widths, and which are formed in the                 longitudinal direction of the tube-grasping body, the                 same direction of the movement of the tube-enlarging                 mandrel; and             -   the width of each of said slits is gradually increased                 from said prescribed width to an expanded width, from a                 prescribed location toward the opening of said tube;     -   the third process wherein         -   the circumferential surface of the enlargement portion of             the tube is firmly grasped and supported by tube-contacting             parts, as the diameter of each of the tube-contacting parts             is reduced in the axial direction to gradually reduce the             expanded width which has been expanded from a prescribed             width from a prescribed position of the slit, by a sliding             means pressing the slopes of the tube-contacting parts,             while sliding, toward the opening of the corresponding tube,             along the same slopes which are slanted in the widening             direction toward the opening of the tube; and     -   the forth process wherein,         -   in the state where the circumferential surface of the             enlargement portion of the tube is firmly grasped and             supported by the tube-contacting parts, the tube-enlarging             mandrel is further inserted into the tube to join the heat             radiating fin and the tube together.

The invention in claim 8 is to provide a heat exchanger production method, utilizing said tube-grasping body for grasping an insert tube in a heat exchanger, wherein

-   -   a bump is formed to extrude from the interior surface of each of         said tube-contacting parts, at the side of the opening, in the         axial direction of the tube; and     -   each of said tube-contacting parts, capable of radially         expanding or axially compressing, is bent to form a smooth curve         with or without a edge on the bent portion, in the radial         direction, from a prescribed location of said slit toward the         opening of the tube, in order to gradually expand the width of         each of said slits from the prescribed width to the expanded         width, from a prescribed location, toward the opening of the         tube.

The invention in claim 9 is to provide a heat exchanger production method, utilizing said tube-grasping body for grasping an insert tube in a heat exchanger, wherein

-   -   a limiting means is installed at said tube-grasping body 3         having tube-contacting parts 3 f when said tube-grasping body 3         is held by the tube-grasping body holder 3 l, in order to limit         the location of the radial expansion or the axial compression of         the tube-contacting parts 3 f of the tube-grasping body 3.

The invention in claim 10 is to provide a heat exchanger production method, utilizing said tube-grasping body for grasping an insert tube in a heat exchanger, wherein

-   -   a sliding means is provided by the guide-pipe 3 c, which moves         back and forth in the longitudinal direction of the tube, along         said slopes 3 b of the tube-contacting parts 3 f; and     -   the maximum exterior diameter 3 v of said tube-grasping body 3         is set below the exterior diameter 3 w of the guide-pipe 3 c,         wherein the maximum exterior diameter 3 v is formed and         configured by the opposing tube-contacting parts 3 f facing each         other in order to build up said slopes 3 b.

The invention in claim 11 is to provide an air-conditioner which is equipped with a heat exchanger produced by a production method, utilizing said tube-grasping body for grasping an insert tube in a heat exchanger.

The invention in claim 12 is to provide an outdoor unit which is used with an air conditioner, and which is equipped with a heat exchanger produced by a production method, utilizing said tube-grasping body for grasping an insert tube in a heat exchanger.

The invention in claim 13 is to provide a heat exchanger production apparatus wherein

-   -   the tube-grasping body is used in a heat exchanger production         apparatus 1;     -   the tube-grasping body is also connectable at the exterior of a         tube-enlarging mandrel 2, for moving back and forth, along said         tube-enlarging mandrel 2 which is penetrable from the opening 7         b of a tube 7 inserted into a heat radiating fin 6 of a heat         exchanger 5;     -   the tube-grasping body is also equipped with a plurality of         tube-contacting parts 3 f, capable of radially expanding or         axially compressing in the cross direction of the longitudinal         length of said tube 7;     -   the tube-grasping body is also equipped with slopes 3 b slanting         gradually in the widening direction toward the opening 7 b of         the corresponding tube, wherein each of the slopes 3 b is formed         on the exterior surface of each of said tube-contacting parts 3         f;     -   the tube-grasping body is also equipped with a sliding means         which radially expands or axially compresses each of said         tube-contacting parts 3 f, by sliding back and forth in the         longitudinal direction of the tube, along said slopes 3 b of the         tube-contacting parts 3 f;     -   a bump 3 e is formed to extrude from the interior surface of         each of said tube-contacting parts 3 f, at the side of the         opening 7 b, in the axial direction of the tube 7;     -   a slope 3 m, which has a straight or curved sloping side, is         formed at said bump 3 e, and slanted in the widening direction,         from the summit 3 p of the bump 3 e, toward the opening 7 b of         the tube 7 facing the end-line 3 o of the tube-contacting part 3         f, in order to prevent said opening 7 b from being deformed by         collision of the bump 3 e with the opening 7 b of the tube 7         when the opening 7 b of the tube 7 is connected at its exterior         to the tube-contacting parts 3 f;     -   a slope 3 g, which has a straight or curved sloping side, is         formed on the interior circumference of said guide-pipe 3 c at         its end side, and slanted in the widening direction toward the         opening 7 b of the corresponding tube 7, in order to reduce the         sliding abrasion against each of the slopes 3 b formed on the         exterior surface of each of said tube-contacting parts 3 f;     -   said slope 3 b is also formed, on the exterior surface of each         of the tube-contacting parts 3 f of said tube-grasping body 3,         at such a position that the slope 3 b is not allowed to reach         the end-line 3 o of each of said tube-contacting parts 3 f; and     -   the tube-grasping body 3 is also characterized by the         configuration wherein         -   said tube-contacting parts 3 f, capable of radially             expanding or axially compressing, are formed and separated             by a plurality of slits 3 a which are of prescribed widths 3             u, and which are formed in the longitudinal direction of the             tube-grasping body 3, the same direction of the movement of             the tube-enlarging mandrel 2; and         -   the width of each of said slits 3 a is gradually increased             from said prescribed width 3 u to an expanded width 3 x,             from a prescribed location toward the opening 7 b of said             tube 7.

The invention in claim 14 is to provide a heat exchanger production apparatus 1, utilizing said tube-grasping body 3, wherein,

-   -   the slope 3 b is formed on the exterior surface of each of said         tube-contacting parts 3 f of said tube-grasping body 3, at the         rear side of the bump 3 e which is formed at the side of the         opening 7 b on the interior surface of each of said         tube-contacting parts 3 f, the opposite side of the end-line 3 o         of the tube-contacting part 3 f, in such a way that said slope 3         b is not allowed to reach the end-line 3 o of each of the         tube-contacting parts 3 f of said tube-grasping body 3.

The invention in claim 15 is to provide a heat exchanger production apparatus 1, utilizing said tube-grasping body 3, wherein

-   -   said tube-grasping body 3 is equipped with a tool-joining part 3         j for joining or disjoining said tube-grasping body 3, to or         from the tube-grasping body holder 3 l.

The invention in claim 16 is to provide a heat exchanger production apparatus 1, utilizing said tube-grasping body 3, wherein

-   -   a limiting means is installed at said tube-grasping body with         tube-contacting parts 3 f when said tube-grasping body 3 is held         by the tube-grasping body holder 3 l, in order to limit the         location of the radial expansion or the axial compression of the         tube-contacting parts 3 f of the tube-grasping body 3 (limiting         rotation of the tube-grasping body holder 3 l).

The invention in claim 17 is to provide a heat exchanger production apparatus 1, utilizing said tube-grasping body 3, wherein

-   -   said sliding means is provided by the guide-pipe 3 c, and     -   said guide-pipe 3 c is equipped with a tool-joining part 3 i for         joining or disjoining the guide-pipe 3 c, to or from the         guide-pipe holder 3 d.

According to the current invention, as the tube-grasping body for grasping an insert tube in a heat exchanger,

-   -   which is used in a heat exchanger production apparatus 1;     -   which is also connectable at the exterior of a tube-enlarging         mandrel 2, for moving back and forth, along said tube-enlarging         mandrel 2 which is penetrable from the opening 7 b of a tube 7         inserted into a heat radiating fin 6 of a heat exchanger 5;     -   which is also equipped with a plurality of tube-contacting parts         3 f, capable of radially expanding or axially compressing in the         cross direction of the longitudinal length of said tube 7;     -   which is also equipped with slopes 3 b slanting gradually in the         widening direction toward the opening 7 b of the corresponding         tube, wherein each of the slopes 3 b is formed on the exterior         surface of each of said tube-contacting parts 3 f; and     -   which also radially expands or axially compresses each of said         tube-contacting parts 3 f, by a sliding means which moves back         and forth in the longitudinal direction of the tube, along said         slopes 3 b of the tube-contacting parts 3 f;         since     -   said tube-contacting parts 3 f, capable of radially expanding or         axially compressing, are formed and separated by a plurality of         slits 3 a which are of prescribed widths 3 u, and which are         formed in the longitudinal direction of the tube-grasping body         3, the same direction of the movement of the tube-enlarging         mandrel 2; and     -   the width of each of said slits 3 a is gradually increased from         said prescribed width 3 u to an expanded width 3 x, from a         prescribed location toward the opening 7 b of said tube 7;         when the side of the opening 7 b of the tube 7 is being         connected at its exterior to the tube-contacting parts 3 f, it         is possible to expand the maximum open diameter 3 y and the         dynamic range of each of the tube-contacting parts 3 f, (said         dynamic range is measured from the difference in diameters         between the expansion and the compression states), through the         plural slits 3 a which are separated by a prescribed width 3 u,         and which are formed in the longitudinal direction of the         tube-grasping body 3 to set up said tube-contacting parts 3 f.         Therefore, even if the exterior diameter 7 i of the enlargement         portion 7 d at the side of the opening 7 b of the tube 7 becomes         about the same size as the interior diameter of the         tube-grasping body 3 itself or the interior diameter between the         tube-contacting parts 3 f (the interior diameter between the         bumps, if bumps are formed), or, even if the axis of the         enlargement portion 7 d is away, by a small degree, relative to         the longitudinal direction of the tube-enlarging mandrel, from         the axis of the tube-grasping body 3, it is possible, by each of         the tube-contacting parts 3 f whose maximum open diameter 3 y         and the dynamic range have been expanded, to provide the effect         of surely preventing one end from being deformed or transformed         by a collision of the end-line of the tube-contacting part 3 f         and the opening 7 b of the tube 7.

Also, according to the tube-grasping body 3 of the current invention, since

-   -   a sliding means is provided by the guide-pipe 3 c, which moves         back and forth in the longitudinal direction of the tube, along         said slopes 3 b of the tube-contacting parts 3 f; and     -   the maximum exterior diameter 3 v of said tube-grasping body 3         is set below the exterior diameter 3 w of the guide-pipe 3 c,         wherein the maximum exterior diameter 3 v is formed and         configured by the opposing tube-contacting parts 3 f facing each         other in order to build up said slopes 3 b,         it is possible to accommodate said tube-contacting parts 3 f,         which are formed and separated by the slits 3 a with a         prescribed width 3 u, within the exterior diameter 3 w of the         guide-pipe 3 c, in the state where the maximum open diameter 3 y         and the dynamic range (the dynamic range is the difference of         the diameters between the expansion and compression states) of         each of the tube-contacting parts 3 f have been expanded through         expansion of each of the widths of the slits 3 a to a larger         value than a prescribed width 3 u. Therefore, it is possible to         provide the effect of surely preventing a collision by         neighboring tube-contacting parts 3 f, even for the following         cases:     -   the case where the space between each of the guide-pipes 3 c is         fully taken up, corresponding to the case where the gap between         branches of the hairpin tube 7, or the gap between each of         neighboring hairpin tubes 7, or the gap between each of straight         tubes being inserted, is significantly reduced comparing to the         prior arts, and     -   the case where the enlargement portion 7 d at the side of the         opening 7 b of the tube 7 is being grasped, by each of the         tube-contacting parts 3 f of each of the tube-grasping bodies 3,         which is accommodated in the interior of each of the neighboring         guide-pipes 3 c.

Also, according to the tube-grasping body 3 of the current invention, since each of said tube-contacting parts 3 f, capable of radially expanding or axially compressing, is bent to form a smooth curve with or without a edge on the bent portion, in the radial direction, from a prescribed location of each of said slits 3 a toward the opening 7 b of the tube 7, in order to gradually expand the width of each of said slits 3 a from the prescribed width 3 u to the expanded width 3 x, from a prescribed location, toward the opening 7 b of the tube 7,

it is possible to increase durability as a component, by smoothly sliding the guide-pipe 3 c along the slope 3 b which is formed on each of the tube-contacting parts 3 f with or without a edge on its sloping side, even if the maximum open diameter 3 y and the dynamic range of each of the tube-contacting parts 3 f (said dynamic range is the difference in diameters between the expansion and the compression states of each of the tube-contacting parts 3 f) are expanded, through the space distance of the expanded widths 3 x, the width expanded from the prescribed width 3 u of the slit 3 a. Also, it is possible to provide the effect of easily and firmly adjusting to maximize the dynamic range of each of the tube-contacting parts 3 f, from the maximum open diameter 3 y to the minimum diameter (till the so-called grasping operation, though the shrinkage in the axial direction in each of the tube-contacting parts 3 f is different, according to the exterior diameter of the enlargement portion of the tube), in proportion to the sliding distance of the guide-pipe 3 c.

Also, according to the tube-grasping body 3 of the current invention, since

-   -   a bump 3 e is formed to extrude from the interior surface of         each of said tube-contacting parts 3 f, at the side of the         opening 7 b, in the axial direction of the tube 7; and     -   a slope 3 m, which has a straight or curved sloping side, is         formed at said bump 3 e, and slanted in the widening direction,         from the summit 3 p of the bump 3 e, toward the opening 7 b of         the tube 7 facing the end-line 3 o of the tube-contacting part 3         f, in order to prevent said opening 7 b from being deformed by         collision of the bump 3 e with the opening 7 b of the tube 7         when the opening 7 b of the tube 7 is connected at its exterior         to the tube-contacting parts 3 f,         even if the opening 7 b of the tube 7 contacts the bump 3 e of         the tube-contacting part, it is possible to enable the bump 3 e         to slide smoothly following the opening 7 b of the tube 7, by         the slope 3 m with the sloping side being straight or curved,         and it is also possible to provide the effect of surely         preventing the opening 7 b of the tube 7 and the tube-contacting         parts 3 f having the bump 3 e, from being deformed or         transformed.

Also, according to the tube-grasping body of the current invention, since

-   -   a limiting means is installed at said tube-grasping body 3         having tube-contacting parts 3 f when said tube-grasping body 3         is held by the tube-grasping body holder 3 l, in order to limit         the location of the radial expansion or the axial compression of         the tube-contacting parts 3 f of the tube-grasping body 3,         for example, even if the gap between each of the end-plates (not         shown in the figure) which is installed near the enlargement         portion 7 d of the tube 7 being inserted into the heat radiating         fin 6 in a heat exchanger 5, or the gap between each of the         neighboring insert tubes 7, is reduced, it is possible to         support and keep the tube-grasping body 3 at such a place that         any one of the tube-grasping body holders 3 l is not allowed to         rotate to contact the tube-contacting parts 3 f of neighboring         tube-grasping bodies 3, when each of the tube-contacting parts 3         f of the tube-grasping body 3 is radially increased in its         diameter. As a result, it is possible to provide the effect of         surely avoiding deformation by collision of each of the         tube-contacting parts 3 f of the neighboring tube-grasping         bodies 3, or deformation of said end-plate of the heat exchanger         5 by said tube-contacting parts 3 f.

Also, according to said guide-pipe 3 c and the tube-grasping body 3 of the current invention, since

-   -   a slope 3 g, which has a straight or curved sloping side, is         formed on the interior circumference of said guide-pipe 3 c at         its end side, and slanted in the widening direction toward the         opening 7 b of the corresponding tube 7, in order to reduce the         sliding abrasion against each of the slopes 3 b formed on the         exterior surface of each of said tube-contacting parts 3 f; and     -   said slope 3 b is also formed, on the exterior surface of each         of the tube-contacting parts 3 f of said tube-grasping body 3,         at such a position that the slope 3 b is not allowed to reach         the end-line 3 o of each of said tube-contacting parts 3 f,         under the condition where the gap between branches of the         hairpin tube or the gap between the neighboring hairpin tubes is         significantly reduced comparing to the prior arts, shrinking of         the diameter of each of the tube-contacting parts 3 f, which is         caused by the movement of the guide-pipe 3 c toward the opening         7 b, can be stopped before said guide-pipe 3 c reaches the         end-line 3 o of the tube-contacting parts 3 f during the         shrinking operation of the diameter in each of the         tube-contacting parts 3 f. Thus, when the exterior diameter 3 q         of the guide-pipe 3 c, which is being connected at the exterior         of the tube-grasping body 3 having the tube-contacting parts 3         f, is determined as the reference diameter (the interior         diameter 3 r of the guide-pipe 3 c when viewed from itself), the         exterior diameter 3 n measured between the summits of the slopes         3 b of the opposing tube-contacting parts 3 f which are faced         each other, and whose diameter is being reduced during the         enlargement through the slits 3 a, it is possible to set the         enlargement-occurring point 3 s, where the diameter of the         tube-contacting parts 3 f becomes to be the exterior diameter 3         n during the compression in the diameter of the tube-contacting         parts 3 f, at the location 3 t, the location shifted from the         end-line 3 o of said tube-contacting parts 3 f toward the side         of the opening 7 b, the opposite side of said end-line 3 o of         the tube-contacting part 3 f. Thus, it is possible to decrease         the interior diameter 3 r of the guide-tube 3 c by the distance         shifted. As a result, the exterior diameter 3 q of the         guide-pipe 3 c is automatically reduced. Also, even if the gap         between branches of the hairpin tube 7, the gap between each of         the neighboring hairpin tubes 7, or the gap between each of the         straight insert tubes is significantly reduced comparing to the         prior arts, it is possible to prevent the guide-pipe 3 c whose         diameter 3 q has been decreased, from being hit by each of the         neighboring guide-pipes 3 c, when the opening 7 b of each of         straight tubes or hairpin tubes is being connected at its         exterior by the tube-contacting parts of the tube-grasping body         3 equipped with said guide-pipe 3 c. Thus, it is possible to         provide an effect of well producing the heat exchanger 5,         wherein the gap between insert tubes is significantly reduced         for the following example cases: the case where the heat         exchanger is downsized (downsized insert pipes, etc.) due to         reasons of saving in energy or cost, the case where straight         tubes or hairpin tubes 7 are inserted in a zigzag pattern, and         the case where straight tubes or hairpin tubes are inserted in         multiple columns such as columns of 3, 4, or etc.

Also, according to the heat exchanger production apparatus 1 of the current invention, as the apparatus wherein

-   -   the tube-grasping body is also connectable at the exterior of a         tube-enlarging mandrel 2, for moving back and forth, along said         tube-enlarging mandrel 2 which is penetrable from the opening 7         b of a tube 7 inserted into a heat radiating fin 6 of a heat         exchanger 5;     -   the tube-grasping body is also equipped with a plurality of         tube-contacting parts 3 f, capable of radially expanding or         axially compressing in the cross direction of the longitudinal         length of said tube 7;     -   the tube-grasping body is also equipped with slopes 3 b slanting         gradually in the widening direction toward the opening 7 b of         the corresponding tube, wherein each of the slopes 3 b is formed         on the exterior surface of each of said tube-contacting parts 3         f;     -   the tube-grasping body is also equipped with a sliding means         which radially expands or axially compresses each of said         tube-contacting parts 3 f, by sliding back and forth in the         longitudinal direction of the tube, along said slopes 3 b of the         tube-contacting parts 3 f;     -   a bump 3 e is formed to extrude from the interior surface of         each of said tube-contacting parts 3 f, at the side of the         opening 7 b, in the axial direction of the tube 7;     -   a slope 3 m, which has a straight or curved sloping side, is         formed at said bump 3 e, and slanted in the widening direction,         from the summit 3 p of the bump 3 e, toward the opening 7 b of         the tube 7 facing the end-line 3 o of the tube-contacting part 3         f, in order to prevent said opening 7 b from being deformed by         collision of the bump 3 e with the opening 7 b of the tube 7         when the opening 7 b of the tube 7 is connected at its exterior         to the tube-contacting parts 3 f;     -   a slope 3 g, which has a straight or curved sloping side, is         formed on the interior circumference of said guide-pipe 3 c at         its end side, and slanted in the widening direction toward the         opening 7 b of the corresponding tube 7, in order to reduce the         sliding abrasion against each of the slopes 3 b formed on the         exterior surface of each of said tube-contacting parts 3 f; and     -   said slope 3 b is also formed, on the exterior surface of each         of the tube-contacting parts 3 f of said tube-grasping body 3,         at such a position that the slope 3 b is not allowed to reach         the end-line 3 o of each of said tube-contacting parts 3 f;         since     -   said tube-contacting parts 3 f, capable of radially expanding or         axially compressing, are formed and separated by a plurality of         slits 3 a which are of prescribed widths 3 u, and which are         formed in the longitudinal direction of the tube-grasping body         3, the same direction of the movement of the tube-enlarging         mandrel 2; and     -   the width of each of said slits 3 a is gradually increased from         said prescribed width 3 u to an expanded width 3 x, from a         prescribed location toward the opening 7 b of said tube 7;         when the side of the opening 7 b of the tube 7 is being         connected at its exterior to the tube-contacting parts 3 f, it         is possible to expand the maximum open diameter 3 y and the         dynamic range of each of the tube-contacting parts 3 f (said         dynamic range is measured from the difference in diameters         between the expansion and the compression states), through the         plural slits 3 a which are separated by a prescribed width 3 u,         and which are formed in the longitudinal direction of the         tube-grasping body 3 to set up said tube-contacting parts 3 f.         Therefore, even if the exterior diameter 7 i of the enlargement         portion 7 d at the side of the opening 7 b of the tube 7 becomes         about the same size as the interior diameter of the         tube-grasping body 3 itself or the interior diameter between the         tube-contacting parts 3 f (the interior diameter between the         bumps, if bumps are formed), or, if the axis of the enlargement         portion 7 d is away, by a small degree, relative to the         longitudinal direction of the tube-enlarging mandrel, from the         axis of the tube-grasping body 3, it is possible, by each of the         tube-contacting parts 3 f whose maximum open diameter 3 y and         the dynamic range have been expanded, to provide the effect of         surely preventing one end from being deformed or transformed by         collision of the end-line of the tube-contacting part 3 f and         the opening 7 b of the tube 7.

According to the current invention, in the heat exchanger production apparatus 1 configured as above, even if the diameter of hairpin tubes 7 in a heat exchanger 5 being enlarged is different according to the spec of the heat exchanger 5, it is possible for the tube-contacting parts 3 f to firmly grasp the tube 7, by adjusting each of the tube-contacting parts 3 f of the tube-grasping body 3 to automatically adapt to the diameter of the tubes through the slits 3 a which are formed between each of said tube-contacting parts 3 f. Also, the bumps 3 e, which are formed at said tube-contacting parts 3 f, press the circumferential surface 7 e of the enlargement portion 7 d at the side of opening 7 b of hairpin tubes 7, in order to build up extruded-parts 7 g extruding in the axial direction of the tube 7. Thus, it is possible to accurately set the reference location of the opening 7 b during the enlargement process so that producing a high precision heat exchanger is possible by the higher precision enlarging process. Also, since the slope 3 b is formed, on the exterior surface of each of the tube-contacting parts 3 f of said tube-grasping body 3, at such a position that said slope 3 b is not allowed to reach the end-line 3 o of each of said tube-contacting parts 3 f, even if the gap between branches of the hairpin tube or the gap between the neighboring hairpin tubes is significantly reduced comparing to the prior arts, shrinking of the diameter of each of the tube-contacting parts 3 f, which is caused by the movement of the guide-pipe 3 c toward the opening 7 b, can be stopped before said guide-pipe 3 c reaches the end-line 3 o of the tube-contacting parts 3 f.

Thus, when the exterior diameter 3 q of the guide-pipe 3 c, which is being connected at the exterior of the tube-grasping body 3 having the tube-contacting parts 3 f, is determined as the reference diameter (the interior diameter 3 r of the guide-pipe 3 c when viewed from itself), the exterior diameter 3 n measured between the summits of the slopes 3 b of the opposing tube-contacting parts 3 f which are faced each other, and whose diameter is being reduced during the enlargement through the slits 3 a, it is possible to set the enlargement-occurring point 3 s, where the diameter of the tube-contacting parts 3 f becomes to be the exterior diameter 3 n during the compression in the diameter of the tube-contacting parts 3 f, at the location 3 t, the location shifted from the end-line 3 o of said tube-contacting parts 3 f toward the side of the opening 7 b, the opposite side of said end-line 3 o of the tube-contacting part. Thus, it is possible to decrease the interior diameter 3 r of the guide-tube 3 c by the distance shifted. As a result, the exterior diameter 3 q of the guide-pipe 3 c is automatically reduced. Also, even if the gap between branches of the hairpin tube 7, the gap between each of the neighboring hairpin tubes 7, or the gap between each of the straight insert tubes is significantly reduced comparing to the prior arts, it is possible to prevent the guide-pipe 3 c whose diameter 3 q has been decreased, from being hit by each of the neighboring guide-pipes 3 c, when the opening 7 b of each of straight tubes or hairpin tubes is being connected at its exterior by the tube-contacting parts of the tube-grasping body 3 equipped with said guide-pipe 3 c. Thus, it is possible to provide an effect of well producing the heat exchanger 5, wherein the gap between insert tubes is significantly reduced for the following example cases: the case where the heat exchanger is downsized (downsized insert pipes, etc.) due to reasons of saving in energy or cost, the case where straight tubes or hairpin tubes 7 are inserted in a zigzag pattern, and the case where straight tubes or hairpin tubes are inserted in multiple columns such as columns of 3, 4, or etc.

Also, according to the current invention, in the heat exchanger production apparatus 1 configured as above, since

-   -   the slope 3 b is formed on the exterior surface of each of said         tube-contacting parts 3 f of said tube-grasping body 3, at the         rear side of the bump 3 e which is formed at the side of the         opening 7 b on the interior surface of each of said         tube-contacting parts 3 f, the opposite side of the end-line 3 o         of the tube-contacting part 3 f, in such a way that said slope 3         b is not allowed to reach the end-line 3 o of each of the         tube-contacting parts 3 f of said tube-grasping body 3,         it is possible to set the enlargement-occurring point 3 s, where         the diameter of the tube-contacting parts 3 f becomes to be the         exterior diameter 3 n during the compression in the diameter of         the tube-contacting parts 3 f, at the location 3 t, the         farthermost location shifted from the end-line 3 o of said         tube-contacting parts 3 f toward the side of the opening 7 b,         the opposite side of said end-line 3 o of the tube-contacting         part. Thus, it is possible to minimize the interior diameter 3 r         of the guide-tube 3 c by the distance shifted. As a result, the         exterior diameter 3 q of the guide-pipe 3 c can be set at a         minimum. Also, even if the gap between branches of the hairpin         tube 7, the gap between each of the neighboring hairpin tubes 7,         or the gap between each of the straight insert tubes is         extremely reduced comparing to the prior arts, it is possible to         prevent the guide-pipe 3 c whose diameter 3 q has been         minimized, from being hit by each of the neighboring guide-pipes         3 c, when the opening 7 b of each of straight tubes or hairpin         tubes is being connected at its exterior by the tube-contacting         parts of the tube-grasping body 3 equipped with said guide-pipe         3 c. Thus, it is possible to provide an effect of best producing         the heat exchanger 5, wherein the gap between insert tubes is         extremely reduced for the following example cases: the case         where the heat exchanger is extremely downsized (extremely         downsized insert pipes, etc.) due to reasons of saving in energy         or cost, the case where straight tubes or hairpin tubes 7 are         inserted in a zigzag pattern, and the case where straight tubes         or hairpin tubes are inserted in multiple columns such as         columns of 3, 4, or etc.

Also, according to the current invention, in the heat exchanger production apparatus 1 configured as above, since

-   -   said tube-grasping body 3 is equipped with a tool-joining part 3         j for joining or disjoining said tube-grasping body 3, to or         from the tube-grasping body holder 3 l,         it is possible to enable quick change of the tube-grasping body         3 which has been worn, by simply connecting a tool, such as a         driver, to the tool-joining part 3 j, and by rotating said tool.         Also, it is possible to provide a special effect of enabling to         change the tube-grasping body 3 easily, firmly, and within a         very short time, adapting to the gap between branches of the         hairpin tube 7, the gap between the neighboring hairpin tubes 7,         or the gap between or the diameter of each of the neighboring         straight insert tubes.

Also, according to the current invention, in the heat exchanger production apparatus 1 configured as above, if

-   -   a limiting means is installed at said tube-grasping body with         tube-contacting parts 3 f when said tube-grasping body 3 is held         by the tube-grasping body holder 3 l, in order to limit the         location of the radial expansion or the axial compression of the         tube-contacting parts 3 f of the tube-grasping body 3,         for example, even if the gap between each of the end-plates (not         shown in the figure) which is installed near the enlargement         portion 7 d of the tube 7 being inserted into the heat radiating         fin 6 in a heat exchanger 5, or the gap between each of the         neighboring insert tubes 7, is reduced, it is possible to         support and keep the tube-grasping body 3 at such a place that         any one of the tube-grasping body holders 3 l is not allowed to         rotate to contact the tube-contacting parts 3 f of neighboring         tube-grasping bodies 3, when each of the tube-contacting parts 3         f of the tube-grasping body 3 is radially increased in its         diameter. As a result, it is possible to provide the effect of         surely avoiding deformation by collision of each of the         tube-contacting parts 3 f of the neighboring tube-grasping         bodies 3, or deformation of said end-plate of the heat exchanger         5 by said tube-contacting parts 3 f.

Also, according to the current invention, in the heat exchanger production apparatus 1 configured as above, since

-   -   said guide-pipe 3 c is equipped with a tool-joining part 3 i for         joining or disjoining the guide-pipe 3 c, to or from the         guide-pipe holder 3 d,         it is possible to enable quick change of the guide-pipe 3 c         which has been worn, by simply rotating a tool, such as driver,         to the tool-joining part 3 i, and by rotating said tool. Also,         it is possible to provide a special effect of enabling to change         the guide-pipe 3 c easily, firmly, and within a very short time,         adapting to the gap between branches of the hairpin tube 7, the         gap between the neighboring hairpin tubes 7, or the gap between         or the diameter of each of the neighboring straight insert         tubes.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a schematic diagram of a heat exchanger production apparatus according to the present invention.

FIG. 2 illustrates an embodiment of the heat exchanger production apparatus of the present invention, where 2A is an enlarged cross-sectional diagram showing major components, 2B is an enlarged diagram showing major components, 2C and 2D are enlarged cross-sectional diagrams of some of major components when insert tubes are enlarged.

FIG. 3 illustrates the status of the slits of the tube-grasping body used in the heat exchanger production apparatus of the present invention, before the slits are opened, wherein 3A is a front view and 3B is a cross-sectional diagram along the H-H line shown in 3A.

FIG. 4 illustrates the guide-pipe used in the heat exchanger production apparatus of the present invention, where 4A is an enlarged diagram, 4B is a front view, and 4C is a cross-sectional diagram along the I-I line shown in 4B.

FIG. 5 illustrates the status of the slits of the tube-grasping body used in the heat exchanger production apparatus of the present invention, before the slits are opened, wherein 5A is a cross-sectional diagram before the insert tube is grasped, and 5B is a cross-sectional diagram after the insert tube is grasped.

FIG. 6 illustrates the status of the slits of the tube-grasping body used in the heat exchanger production apparatus of the present invention, after the slits are opened, wherein 6A is a front view, and 6B is a cross-sectional diagram along the L-L line shown in 6A.

FIG. 7 illustrates the status of the slits of the tube-grasping body used in the heat exchanger production apparatus of the present invention, after the slits are opened, wherein 7A is a cross-sectional diagram when an insert tube is grasped if the axis of the insert tube is skewed off from the axis of the tube-grasping body, and 7B is a cross-sectional diagram when an insert tube with a large diameter is grasped.

FIG. 8 illustrates an example embodiment of the slits of the tube-grasping body used in the heat exchanger production apparatus of the current invention, after the slits are opened.

FIG. 9 illustrates another example embodiment of the slits of the tube-grasping body used in the heat exchanger production apparatus of the current invention, after the slits are opened.

FIG. 10 illustrates an example embodiment of a product which is equipped with the heat exchanger, produced using the tube-grasping body used in the heat exchanger production apparatus of the current invention, wherein 10A is an air-conditioner having the heat exchanger and 10B is an outdoor unit having the heat exchanger to be used with an air-conditioner.

FIG. 11 illustrates an enlarged cross-sectional diagram of some of major components of the enclosing bodies, which is used in a heat exchanger production apparatus according to the prior arts.

FIG. 12 illustrates a heat exchanger production apparatus of the prior arts, wherein 12A is an enlarged front view when the insert tube is enlarged, 12B is a perspective diagram of the clamp, and 12C is a perspective diagram of another embodiment of the clamp.

DETAILED DESCRIPTION OF THE INVENTION

The current invention relates to a tube-grasping body for grasping an insert tube in a heat exchanger, heat exchanger production methods and apparatuses utilizing the tube-grasping body, and an air-conditioner and/or its outdoor unit with a heat exchanger produced by the method or the apparatus. In the following paragraphs, an embodiment of the current invention is explained.

The embodiment explained here relates to production of the following heat exchangers as examples:

-   -   a heat exchanger which is downsized, utilizing the heat         exchanger production apparatus which is equipped with a         guide-pipe as a sliding means, and which is also equipped with a         tube-grasping body being connected at its exterior to said         guide-pipe for enabling said guide-pipe to slide along said         tube-grasping body, and     -   a heat exchanger wherein the diameters of insert tubes are         different or the gap between each of the tubes is significantly         reduced.         However, in association with said heat exchanger production         apparatus, the parts, which are identical to the prior arts, are         not explained. Separate explanation is provided later about an         embodiment of a tube-grasping body, wherein the slit with a         prescribed width is gradually expanded to an expanded width from         a prescribed location toward the opening of the tube, since its         effect is different from that of an embodiment of a         tube-grasping body with the slits which are not expanded in         their widths.

First, in FIG. 1, it is explained about an embodiment of the heat exchanger production apparatus to implement the heat exchanger production method, the method having a guide-pipe and a tube-contacting part itself of the tube-grasping body for grasping an insert tube in a heat exchanger. The component-loading platform 1 c loads a heat exchanger where the gap between branches of each of insert tubes or the gap between neighboring hairpin tubes 7 is significantly reduced, due to the following reasons:

-   -   the heat exchanger being downsized (by downsized tubes, or etc.)         due to the problems of saving in energy or cost,     -   hairpin tubes 7 being inserted into the heat radiating fin 6 in         a zigzag pattern (not shown in the figure), and     -   hairpin tubes 7 being inserted in multiple columns such as         columns of 3, 4, or etc. (not shown in the figure).         Subsequently, said heat exchanger 5 is pressed and fixed between         the component-loading platform 1 c and the pressing-plate 11 by         lowering the pressing-plate 11 located above.

Next, the base plane 4 d is advanced (not shown in the figure) along the guide rail 12, by operating the round-trip cylinder 4 f of the enclosing-body shifting device 4. At the same time, the driving-cylinder 4 e is operated, in order to enclose each of the hairpin part 7 c extruded from the heat radiating fin 6 of the heat exchanger 5, as indicated in FIG. 11, by the tongue shaped concavity 4 g which resembles a tongue when viewed from the plane of a pair of enclosing-bodies 4 a. Corresponding to said tongue shaped concavity 4 g, the tongue shaped convexity 4 c, which resembles a tongue when viewed from said plane, is formed on the interior surface of said tongue shaped concavity 4 g. Said tongue shaped convexity 4 c turns around the U-shaped interior circumferential surface of said hairpin part 7 c in order to firmly stop shrinkage of the hairpin tube 7 during the enlarging process.

Next, from the opening 7 b of each of said hairpin tubes 7, as shown in FIG. 2( c), by inserting (the arrow A) each of the tube-enlarging mandrels 2 by a prescribed depth, the enlargement portion 7 d with a prescribed length is formed. Subsequently, by advancing (the arrow B) the tube-grasping body 3, by the tube-grasping body holder 3 l, toward the circumferential surface 7 e of said enlargement portion 7 d, from the opening 7 b of the hairpin tube 7, the tube-grasping body 3 is connected to the circumferential surface 7 e, in the state where the exterior of said circumferential surface 7 e is surrounded by the tube-contacting parts 3 f.

Afterwards, if the guide-pipe 3 c is moved (the arrow C), by the guide-pipe holder 3 d, in the same direction of the movement of the tube-enlarging mandrel 2, the guide-pipe 3 c presses the slope 3 b while sliding along the same slope which has been formed on the exterior surface of each of said tube-contacting parts 3 f, and which is slanted in the widening direction toward the opening 7 b of the corresponding tube 7. Thus, the diameter of each of the tube-contacting parts 3 f is reduced in the axial direction of the tube-enlarging mandrel 2, by the space isolation of the prescribed width 3 u of the slits 3 a. As a result, each of said tube-contacting parts 3 f becomes tightly connected at its exterior to the guide-pipe 3 c, and, therefore, each of said tube-contacting parts 3 f becomes to firmly grasp and support the circumferential surface 7 e of the enlargement portion 7 d of the hairpin tube 7. The tube-grasping body 3 with such guide-pipe 3 c and tube-contacting parts 3 f is shown in FIGS. 3-5, which are explained later. Specially, as shown in FIG. 2( d), a bump 3 e is formed at each of the tube-contacting parts 3 f for pressing (the arrow D) the circumferential surface 7 e of said enlargement portion 7 d (though the bump explained in FIG. 2( d) is little different in its shape from the bump 3 e in FIGS. 3-5, their functions are the same), at the position where each of the tube-contacting parts meets the enlargement portion 7 d of the hairpin tube 7, in order to build up the extruded-part 7 g extruding from the interior circumferential surface 7 f of said hairpin 7, in the axial direction of the tube-enlarging mandrel 2. Thus, the circumferential surface 7 e of the enlargement portion 7 d becomes more firmly grasped and supported. Therefore, it is possible to surely set the reference location of the opening 7 b during the enlargement process. Next, from this state, if said tube-enlarging mandrel 2 is moved toward the hairpin part 7 c of the hairpin tube 7, both of the hairpin part 7 c and the opening 7 b are supported. Thus, it is possible to keep shrinkage of the entire length of the hairpin tubes 7 at a minimum, and it is also possible to produce a high quality heat exchanger having higher precision.

Also, when producing a heat exchanger where the gap between branches of the insert tube or the gap between neighboring hairpin tubes is significantly reduced, since the heat exchanger production apparatus 1 having the tube-grasping body 3 and the guide-pipe 3 c indicated in FIGS. 3-5 is configured by the following conditions wherein

-   -   the tube-grasping body is also connectable at the exterior of a         tube-enlarging mandrel 2, for moving back and forth, along said         tube-enlarging mandrel 2 which is penetrable from the opening 7         b of a tube 7 inserted into a heat radiating fin 6 of a heat         exchanger 5;     -   the tube-grasping body is also equipped with a plurality of         tube-contacting parts 3 f, capable of radially expanding or         axially compressing in the cross direction of the longitudinal         length of said tube 7;     -   the tube-grasping body is also equipped with slopes 3 b slanting         gradually in the widening direction toward the opening 7 b of         the corresponding tube, wherein each of the slopes 3 b is formed         on the exterior surface of each of said tube-contacting parts 3         f;     -   the tube-grasping body is also equipped with a sliding means         which radially expands or axially compresses each of said         tube-contacting parts 3 f, by sliding back and forth in the         longitudinal direction of the tube, along said slopes 3 b of the         tube-contacting parts 3 f;     -   a bump 3 e is formed to extrude from the interior surface of         each of said tube-contacting parts 3 f, at the side of the         opening 7 b, in the axial direction of the tube 7;     -   a slope 3 m, which has a straight or curved sloping side, is         formed at said bump 3 e, and slanted in the widening direction,         from the summit 3 p of the bump 3 e, toward the opening 7 b of         the tube 7 facing the end-line 3 o of the tube-contacting part 3         f, in order to prevent said opening 7 b from being deformed by         collision of the bump 3 e with the opening 7 b of the tube 7         when the opening 7 b of the tube 7 is connected at its exterior         to the tube-contacting parts 3 f;     -   a slope 3 g, which has a straight or curved sloping side, is         formed on the interior circumference of said guide-pipe 3 c at         its end side, and slanted in the widening direction toward the         opening 7 b of the corresponding tube 7, in order to reduce the         sliding abrasion against each of the slopes 3 b formed on the         exterior surface of each of said tube-contacting parts 3 f; and     -   said slope 3 b is also formed, on the exterior surface of each         of the tube-contacting parts 3 f of said tube-grasping body 3,         at such a position that the slope 3 b is not allowed to reach         the end-line 3 o of each of said tube-contacting parts 3 f;         even if the diameter of the hairpin tube 7 in a heat exchanger 5         being enlarged is different according to the spec of the heat         exchanger 5, for example, as shown in FIG. 5, by advancing the         tube-grasping body 3, by the tube-grasping body holder 3 l (not         shown in the figure), toward the enlargement portion 7 d of the         tube 7 having a reference diameter of a prescribed tube diameter         7 h, the tube-grasping body 3 becomes connected to the exterior         of said tube 7. Then, by advancing said guide-pipe 3 c (the         arrow J), by the guide-pipe holder 3 c (not shown in the         figure), toward the opening 7 b of the tube 7, each of         tube-contacting parts 3 f of said tube-grasping body 3 becomes         to grasp the enlargement portion 7 d of the tube 7 with a         prescribed diameter 7 h, by shrinking (the arrow K) of the         diameter of each of tube-contacting parts 3 f of said         tube-grasping body 3, through the space distance of the slits 3         a which are formed between said tube-contacting parts 3 f, and         which are of prescribed widths 3 u. Also, the bumps 3 e, which         are formed at said tube-contacting parts 3 f, press the         circumferential surface 7 e of the enlargement portion 7 d and         build up the extruded-parts 7 g (not shown in the figure)         extruding in the axial direction of the tube 7. Thus, the         tube-contacting parts become to firmly grasp and support the         tube, and, therefore, it is possible to accurately set the         reference point of the opening 7 b during the enlarging process,         in order to produce a high precision heat exchanger by the         higher precision enlarging process. Also, even if the gap         between branches of the hairpin tube 7 or the gap between         neighboring hairpin tubes is significantly reduced comparing to         the prior arts, since the slope 3 b is formed, on the exterior         surface of each of the tube-contacting parts 3 f of said         tube-grasping body 3, at such a position that said slope 3 b is         not allowed to reach the end-line 3 o of each of said         tube-contacting parts 3 f, during the phase where the diameter         of each of the tube-contacting parts 3 f is being reduced,         shrinking of the diameter of each of the tube-contacting parts 3         f, which is caused by the movement of the guide-pipe 3 c toward         the opening 7 b, can be stopped before said guide-pipe 3 c         reaches the end-line 3 o of the tube-contacting parts 3 f.

Thus, when the exterior diameter 3 q of the guide-pipe 3 c, which is being connected at the exterior of the tube-grasping body 3 having the tube-contacting parts 3 f, is determined as the reference diameter (the interior diameter 3 r of the guide-pipe 3 c when viewed from itself), the exterior diameter 3 n measured between summits of the slopes 3 b of the opposing tube-contacting parts 3 f which are faced each other, and whose diameter is being reduced during the enlargement through the slits 3 a, it is possible to set the enlargement-occurring point 3 s, where the diameter of the tube-contacting parts 3 f becomes to be the exterior diameter 3 n during the compression in the diameter of the tube-contacting parts 3 f, at the location 3 t, the location shifted from the end-line 3 o of said tube-contacting parts 3 f toward the side of the opening 7 b, the opposite side of said end-line 3 o of the tube-contacting part. Thus, it is possible to decrease the interior diameter 3 r of the guide-tube 3 c by the distance shifted. As a result, the exterior diameter 3 q of the guide-pipe 3 c is automatically reduced. Also, even if the gap between branches of the hairpin tube 7, the gap between each of the neighboring hairpin tubes 7, or the gap between each of the straight insert tubes is significantly reduced comparing to the prior arts, it is possible to prevent the guide-pipe 3 c whose diameter 3 q has been decreased, from being hit by each of the neighboring guide-pipe 3 c, when the opening 7 b of each of straight tubes or hairpin tubes is being connected at its exterior by the tube-contacting parts of the tube-grasping body 3 equipped with said guide-pipe 3 c. Thus, it is possible to provide an effect of well producing the heat exchanger 5, wherein the gap between insert tubes is significantly reduced for the following example cases: the case where the heat exchanger is downsized (downsized insert tubes, etc.) due to reasons of saving in energy or cost, the case where straight tubes or hairpin tubes 7 are inserted in a zigzag pattern, and the case where straight tubes or hairpin tubes are inserted in multiple columns such as columns of 3, 4, or etc.

Also, relating to FIGS. 3-5, if the slope 3 b is formed on the exterior surface of each of said tube-contacting parts 3 f of said tube-grasping body 3, at the rear side of the bump 3 e which is formed at the side of the opening 7 b on the interior surface of each of said tube-contacting parts 3 f, the opposite side of the end-line 3 o of the tube-contacting part 3 f, in such a way that said slope 3 b is not allowed to reach the end-line 3 o of the tube-contacting part 3 f of said tube-grasping body 3, it is possible to set the enlargement-occurring point 3 s, where the diameter of the tube-contacting parts 3 f becomes to be the exterior diameter 3 n during the compression in the diameter of the tube-contacting parts 3 f, at the location 3 t, the farthermost location shifted from the end-line 3 o of said tube-contacting parts 3 f toward the side of the opening 7 b, the opposite side of said end-line 3 o of the tube-contacting part 3 f. Thus, it is possible to minimize the interior diameter 3 r of the guide-tube 3 c by the distance shifted. As a result, the exterior diameter 3 q of the guide-pipe 3 c can be set at a minimum. Also, even if the gap between branches of the hairpin tube 7, the gap between each of the neighboring hairpin tubes 7, or the gap between each of the straight insert tubes is extremely reduced comparing to the prior arts, it is possible to prevent the guide-pipe 3 c whose diameter 3 q has been minimized, from being hit by each of the neighboring guide-pipe 3 c, when the opening 7 b of each of straight tubes or hairpin tubes is being connected at its exterior by the tube-contacting parts of the tube-grasping body 3 equipped with said guide-pipe 3 c. Thus, it is possible to provide an effect of best producing the heat exchanger 5, wherein the gap between insert tubes is extremely reduced for the following example cases: the case where the heat exchanger is extremely downsized (extremely downsized insert tubes, etc.) due to reasons of saving in energy or cost, the case where straight tubes or hairpin tubes 7 are inserted in a zigzag pattern, and the case where straight tubes or hairpin tubes are inserted in multiple columns such as columns of 3, 4, or etc.

Also, according to the tube-grasping body 3 configured as above, if said tube-grasping body 3 is equipped with a tool-joining part 3 j for joining or disjoining said tube-grasping body 3, to or from the tube-grasping body holder 3 l, it is possible to enable quick change of the tube-grasping body 3 which has been worn, by simply connecting a tool, such as a driver, to the tool-joining part 3 j, and by rotating said tool. Also, it is possible to provide an effect of enabling to change the tube-grasping body 3 easily, firmly, and within a very short time, perfectly adapting to the gap between branches of the hairpin tube 7, the gap between the neighboring hairpin tubes 7, or the gap between or the diameter of each of the neighboring straight insert tubes.

Also, relating to the guide-pipe 3 c configured as above, if said guide-pipe 3 c is equipped with a tool-joining part 3 i for joining or disjoining the guide-pipe 3 c, to or from the guide-pipe holder 3 d, it is possible to enable quick change of the guide-pipe 3 c which has been worn, by simply rotating a tool, such as driver, to the tool-joining part 3 i, and by rotating said tool. Also, it is possible to provide a special effect of enabling to change the guide-pipe 3 c easily, firmly, and within a very short time, perfectly adapting to the gap between branches of the hairpin tube 7, the gap between the neighboring hairpin tubes 7, or the gap between or the diameter of each of the neighboring straight insert tubes.

Next, relating to the tube-grasping body of the current invention for grasping an insert tube in a heat exchanger, an embodiment of the tube-grasping-body equipped with the tube-contacting parts 3 f is explained, wherein the slits are formed for building up said contacting parts 3 f, and the width of each of the slits is gradually increased from a prescribed width to an expanded width, from a prescribed location of the slit.

In FIG. 6, in a heat exchanger production apparatus to embody the heat exchanger production method explained above, utilizing the tube-grasping body 3 which is also connectable at the exterior of a tube-enlarging mandrel 2, for moving back and forth, along said tube-enlarging mandrel 2 which is penetrable from the opening 7 b of a tube 7 inserted into a heat radiating fin 6 of a heat exchanger 5;

-   -   which is also equipped with a plurality of tube-contacting parts         3 f, capable of radially expanding or axially compressing in the         cross direction of the longitudinal length of said tube 7;     -   which is also equipped with slopes 3 b slanting gradually in the         widening direction toward the opening 7 b of the corresponding         tube, wherein each of the slopes 3 b is formed on the exterior         surface of each of said tube-contacting parts 3 f;     -   which also radially expands or axially compresses each of said         tube-contacting parts 3 f, by a sliding means which moves back         and forth in the longitudinal direction of the tube, along said         slopes 3 b of the tube-contacting parts 3 f; and     -   which is also characterized by the configuration wherein         -   said tube-contacting parts 3 f, capable of radially             expanding or axially compressing, are formed and separated             by a plurality of slits 3 a which are of prescribed widths 3             u, and which are formed in the longitudinal direction of the             tube-grasping body 3, the same direction of the movement of             the tube-enlarging mandrel 2;             if the width of each of said slits 3 a is gradually             increased from said prescribed width 3 u to an expanded             width 3 x, from a prescribed location toward the opening 7 b             of said tube 7, when the side of the opening 7 b of the tube             7 is being connected at its exterior to the tube-contacting             parts 3 f, it is possible to greatly expand (the arrow M)             the maximum open diameter 3 y and the dynamic range (space             distance) of each of the tube-contacting parts 3 f (said             dynamic range is measured from the difference in diameters             between the expansion and the compression states), through             the plural slits 3 a which are separated by a prescribed             width 3 u, and which are formed in the longitudinal             direction of the tube-grasping body 3 to build up said             tube-contacting parts 3 f.

Therefore, as shown in FIG. 7( a), for example, even if the axis of the enlargement portion 7 d of the tube 7 having a prescribed diameter 7 h is away, by a small degree, relative to the longitudinal direction of the tube-enlarging mandrel, from the axis of the tube-grasping body 3, it is possible, by each of the tube-contacting parts 3 f whose maximum open diameter 3 y and the dynamic range (the dynamic range being measured from the difference in diameters between the expansion and the compression states) have been greatly expanded, to provide the effect of surely preventing one end from being deformed or transformed by collision of the end-line of the tube-contacting part 3 f and the opening 7 b of the tube 7.

Also, as shown in FIG. 7( b), if the width of each of said slits 3 a of the tube-grasping body 3 is gradually increased from said prescribed width 3 u to an expanded width 3 x, from a prescribed location toward the opening 7 b of said tube 7, it is possible, by each of the tube-contacting parts 3 f whose maximum open diameter 3 y and the dynamic range have been expanded (the dynamic range is measured from the difference between diameters of the expansion and compression states), to provide the effect of surely preventing one end from being deformed or transformed by collision of the end-line of the tube-contacting part 3 f and the opening 7 b of the tube 7 even if the exterior diameter 7 i of the enlargement portion 7 d at the side of the opening 7 b of the tube 7 becomes about the same size (bigger diameter than the reference diameter of a prescribed diameter 7 h) as the interior diameter of the tube-grasping body 3 itself or the interior diameter between the tube-contacting parts 3 f (the interior diameter between the bumps, if bumps are formed).

Also, relating to the tube-grasping body 3 configured above, if each of said tube-contacting parts 3 f, capable of radially expanding or axially compressing, is bent to form a smooth curve with or without a edge on the bent portion, in the radial direction, from a prescribed location of said slit 3 a toward the opening 7 b of the tube 7, in order to gradually expand the width of each of said slits 3 a from the prescribed width 3 u to the expanded width 3 x, from a prescribed location, toward the opening 7 b of the tube 7, it is possible to increase durability as a component, by smoothly sliding the guide-pipe 3 c along said slope 3 b which is formed on each of the tube-contacting parts 3 f with or without a edge on its sloping side, even if the maximum open diameter 3 y and the dynamic range (said dynamic range is the difference in diameters between the expansion and the compression states) of each of the tube-contacting parts 3 f are maximally expanded, through the space distance of the expanded widths 3 x, the width expanded from the prescribed width 3 u of the slit 3 a. Also, it is possible to provide the effect of easily and firmly adjusting to maximize the dynamic range of each of the tube-contacting parts 3 f, from the maximum open diameter 3 y to the minimum diameter (till the so-called grasping operation, though the shrinkage in the axial direction in each of the tube-contacting parts 3 f is different, according to the exterior diameter of the enlargement portion of the tube), in proportion to the sliding distance of the guide-pipe 3 c.

Also, relating to the tube-grasping body 3 configured as above, since

-   -   a bump 3 e is formed to extrude from the interior surface of         each of said tube-contacting parts 3 f, at the side of the         opening 7 b, in the axial direction of the tube 7; and     -   a slope 3 m, which has a straight or curved sloping side, is         formed at said bump 3 e, and slanted in the widening direction,         from the summit 3 p of the bump 3 e, toward the opening 7 b of         the tube 7 facing the end-line 3 o of the tube-contacting part 3         f, in order to prevent said opening 7 b from being deformed by         collision of the bump 3 e with the opening 7 b of the tube 7         when the opening 7 b of the tube 7 is connected at its exterior         to the tube-contacting parts 3 f,         even if the opening 7 b of the tube 7 contacts the bump 3 e of         each of the tube-contacting parts 3 f, it is possible to enable         the bump 3 e to slide smoothly following the opening 7 b of the         tube 7, by the slope 3 m with the sloping side being straight or         curved, and it is also possible to provide the effect of surely         preventing the opening 7 b of the tube 7 and the tube-contacting         parts 3 f having the bump 3 e, from being deformed or         transformed.

Also, relating to the tube-grasping body 3 and the guide-pipe 3 c, configured as above, since

-   -   a slope 3 g, which has a straight or curved sloping side, is         formed on the interior circumference of said guide-pipe 3 c at         its end side, and slanted in the widening direction toward the         opening 7 b of the corresponding tube 7, in order to reduce the         sliding abrasion against each of the slopes 3 b formed on the         exterior surface of each of said tube-contacting parts 3 f; and     -   said slope 3 b is also formed, on the exterior surface of each         of the tube-contacting parts 3 f of said tube-grasping body 3,         at such a position that the slope 3 b is not allowed to reach         the end-line 3 o of each of said tube-contacting parts 3 f,         under the condition where the gap between branches of the         hairpin tube or the gap between the neighboring hairpin tubes is         significantly reduced comparing to the prior arts, shrinking of         the diameter of each of the tube-contacting parts 3 f, which is         caused by the movement of the guide-pipe 3 c toward the opening         7 b, can be stopped before said guide-pipe 3 c reaches the         end-line 3 o of the tube-contacting parts 3 f during the         shrinking operation of the diameter in each of the         tube-contacting parts 3 f. Thus, when the exterior diameter 3 q         of the guide-pipe 3 c, which is connected at the exterior of the         tube-grasping body 3 having the tube-contacting parts 3 f, is         determined as the reference diameter (the interior diameter 3 r         of the guide-pipe 3 c when viewed from itself), the exterior         diameter 3 n measured between the summits of the slopes 3 b of         the opposing tube-contacting parts 3 f which are faced each         other, and whose diameter is being reduced during the         enlargement through the slits 3 a, it is possible to set the         enlargement-occurring point 3 s, where the diameter of the         tube-contacting parts 3 f becomes to be the exterior diameter 3         n during the compression in the diameter of the tube-contacting         parts 3 f, at the location 3 t, the location shifted from the         end-line 3 o of said tube-contacting parts 3 f toward the side         of the opening 7 b, the opposite side of said end-line 3 o of         the tube-contacting part 3 f. Thus, it is possible to decrease         the interior diameter 3 r of the guide-tube 3 c by the distance         shifted. As a result, the exterior diameter 3 q of the         guide-pipe 3 c is automatically reduced. Also, even if the gap         between branches of the hairpin tube 7, the gap between each of         the neighboring hairpin tubes 7, or the gap between each of the         straight insert tubes is significantly reduced comparing to the         prior arts, it is possible to prevent the guide-pipe 3 c whose         diameter 3 q has been decreased, from being hit by each of the         neighboring guide-pipes 3 c, when the opening 7 b of each of         straight tubes or hairpin tubes is being connected at its         exterior by the tube-contacting parts of the tube-grasping body         3 equipped with said guide-pipe 3 c. Thus, it is possible to         provide an effect of well producing the heat exchanger 5,         wherein the gap between insert tubes is significantly reduced         for the following example cases: the case where the heat         exchanger is downsized (downsized insert pipes, etc.) due to         reasons of saving in energy or cost, the case where straight         tubes or hairpin tubes 7 are inserted in a zigzag pattern, and         the case where straight tubes or hairpin tubes are inserted in         multiple columns such as columns of 3, 4, or etc.

Also, as shown in FIG. 8, relating to said tube-grasping body 3, since

-   -   a sliding means is provided by the guide-pipe 3 c, which moves         back and forth in the longitudinal direction of the tube, along         said slopes 3 b of the tube-contacting parts 3 f; and     -   the maximum exterior diameter 3 v of said tube-grasping body 3         is set below the exterior diameter 3 w of the guide-pipe 3 c,         wherein the maximum exterior diameter 3 v is formed and         configured by the opposing tube-contacting parts 3 f facing each         other in order to build up said slopes 3 b,         it is possible to accommodate said tube-contacting parts 3 f,         which are formed and separated by the slits 3 a with a         prescribed width 3 u, within the exterior diameter 3 w of the         guide-pipe 3 c, in the state where the maximum open diameter 3 y         and the dynamic range (the dynamic range is the difference in         diameters between the expansion and compression states) of each         of the tube-contacting parts 3 f are expanded through expansion         of each of the widths of the slits 3 a to a larger value than a         prescribed width 3 u. Therefore, it is possible to provide the         effect of surely preventing collision by neighboring         tube-contacting parts 3 f, even for the following cases:     -   the case where the space between each of the guide-pipes 3 c is         fully taken up, corresponding to the case where the gap between         branches of the hairpin tube 7, or the gap between each of         neighboring hairpin tubes 7, or the gap between each of straight         tubes being inserted, is significantly reduced comparing to the         prior arts, and     -   the case where the enlargement portion 7 d at the side of the         opening 7 b of the tube 7 is being grasped, by each of the         tube-contacting parts 3 f of each of the tube-grasping bodies 3,         which is accommodated in the interior of each of the neighboring         guide-pipes 3 c.

Also, as indicated in FIG. 9, at the tube-grasping body 3 with said tube-contacting parts 3 f, if a limiting means such as a groove or a concavity (not shown in the figure) or a convexity (not shown in the figure) is installed when said tube-grasping body 3 is held by the tube-grasping body holder 3 l, in order to limit (limiting rotation of the tube-grasping body holder 3 l) the location of the radial expansion or the axial compression of the tube-contacting parts 3 f of the tube-grasping body 3 (though not shown in the figure, parts which correspond to the limiting means of the tube-grasping body 3, and which are fixed at the tube-grasping holder 3 l or other components, are contacted and limited by such limiting means), it is possible to support and keep the tube-grasping body 3 at such a place that none of the tube-grasping body holders 3 l is allowed to rotate to contact the tube-contacting parts 3 f of neighboring tube-grasping bodies 3, when each of the tube-contacting parts 3 f of the tube-grasping body 3 is radially increased in its diameter, even if the gap between each of the end-plates (not shown in the figure) which is installed near the enlargement portion 7 d of the tube 7 being inserted into the heat radiating fin 6 in a heat exchanger 5, or the gap between each of the neighboring insert tubes 7, is reduced. As a result, it is possible to provide the effect of surely avoiding deformation by collision of each of the tube-contacting parts 3 f of the neighboring tube-grasping bodies 3, or deformation of said end-plate of the heat exchanger 5 by said tube-contacting parts 3 f.

If the width of each of said slits 3 a is gradually increased from said prescribed width 3 u to an expanded width 3 x, from a prescribed location toward the opening 7 b of said tube 7, when the side of the opening 7 b is being connected at its exterior to the tube-contacting parts 3 f, it is possible to expand the maximum open diameter 3 y and the dynamic range of each of the tube-contacting parts 3 f (the dynamic range is measured from the difference in diameters between the expansion and the compression states), through the plural slits 3 a which are separated by a prescribed width 3 u, and which are formed in the longitudinal direction of the tube-grasping body 3 to set up said tube-contacting parts 3 f; when producing a heat exchanger by the heat exchanger production method comprising:

-   -   the first process wherein         -   an enlargement portion having a prescribed length is formed,             by inserting a tube-enlarging mandrel by a prescribed depth,             from the opening of an insert tube being inserted into a             heat radiating fin of a heat exchanger;     -   the second process wherein         -   the exterior of said enlargement portion is surrounded and             connected, by     -   the tube-grasping body wherein         -   -   said tube-contacting parts, capable of radially                 expanding or axially compressing, are formed and                 separated by a plurality of slits which are of                 prescribed widths, and which are formed in the                 longitudinal direction of the tube-grasping body, the                 same direction of the movement of the tube-enlarging                 mandrel; and             -   the width of each of said slits is gradually increased                 from said prescribed width to an expanded width, from a                 prescribed location toward the opening of said tube;     -   the third process wherein         -   the circumferential surface of the enlargement portion of             the tube is firmly grasped and supported by tube-contacting             parts, as the diameter of each of the tube-contacting parts             is reduced in the axial direction to gradually reduce the             expanded width which has been expanded from a prescribed             width from a prescribed position of the slit, by a sliding             means pressing the slopes of the tube-contacting parts,             while sliding, toward the opening of the corresponding tube,             along the same slopes which are slanted in the widening             direction toward the opening of the tube; and     -   the forth process wherein,         -   in the state where the circumferential surface of the             enlargement portion of the tube is firmly grasped and             supported by the tube-contacting parts, the tube-enlarging             mandrel is further inserted into the tube to join the heat             radiating fin and the tube together.

Thus, as explained in FIG. 7( a) above, for example, even if the axis of the enlargement portion 7 d of the said tube 7 having a reference diameter of a prescribed tube diameter 7 h is away, by a small degree, relative to the longitudinal direction of the tube-enlarging mandrel 2, from the axis of the tube-grasping body 3, it is possible, by each of the tube-contacting parts 3 f whose maximum open diameter 3 y and the dynamic range (the dynamic range is measured from the difference of the diameters between the expansion and compression states) have been greatly expanded, to provide the effect of surely preventing one end from being deformed or transformed by a collision of the end-line of the tube-contacting part 3 f and the opening 7 b of the tube 7.

Also, relating to the case where a heat exchanger is produced by the method above, as shown in FIG. 7( b), if the width of each of said slits 3 a of the tube-grasping body 3 is gradually increased from said prescribed width 3 u to an expanded width 3 x, from a prescribed location toward the opening 7 b of said tube 7, it is possible, by each of the tube-contacting parts 3 f whose maximum open diameter 3 y and the dynamic range (the dynamic range is measured from the difference of the diameters between the expansion and compression states) have been expanded, to provide the effect of surely preventing one end from being deformed or transformed by collision of the end-line of the tube-contacting part 3 f and the opening 7 b of the tube 7, even if the exterior diameter 7 i of the enlargement portion 7 d at the side of the opening 7 b of the tube 7 becomes about the same size (bigger than the reference diameter of a prescribed diameter 7 h) as the interior diameter of the tube-grasping body 3 itself or the interior diameter between the tube-contacting parts 3 f (the interior diameter between the bumps, if bumps are formed).

Thus, if a heat exchanger 5, produced by the method using the tube-grasping body, is placed in a prescribed casing 20 a with various components such as an air blower (FIG. 10( a)), or, in an outdoor unit 21 used in an air conditioner 20 (FIG. 10( b)), the products adopting such a heat exchanger enables a decrease in logistics cost or product cost, due to the downsized heat exchanger due to the decrease in the tube diameter, or the gap between neighboring tubes.

Also, relating to the case where the heat exchanger, produced by the method of the current invention explained above, is used in an air conditioner 20 or in an outdoor unit 21 used in an air conditioner 20, it is not implied to exclude air conditioners such as a so-called centralized air conditioner which is referred to as either an air handling unit or a fan coil unit, or a so-called individual air conditioner which is referred to as either a package air conditioner or a room air conditioner. Thus, for any air conditioner using a heat exchanger, it is not implied to exclude anything such as its detailed configuration, the shape, the size, the system construction. Also, it does not exclude anything such as its use or sales area, if a heat exchanger produced by the method of the current invention is used in other various products.

Also, for an embodiment where tubes other than hairpin tubes are inserted, for example, for the case where multiple straight tubes (not shown in the figure) are inserted, it is not implied to limit anything such as the tube material, the shape, kinds, quantity, the insertion pattern, and etc.

Also, relating to the embodiment explained above, though a so-called vertical typed enlargement apparatus is explained, as an example of the heat exchanger production apparatus with the tube-grasping body 3 which is connected at its exterior to the guide-pipe 3 c to enable the guide-pipe to slide along said tube-grasping body, it is not implied to exclude a so-called horizontal typed enlargement apparatus. Also, relating to the so-called vertical typed enlargement apparatus, it is not implied to exclude anything such as detailed configuration, kinds, characteristics, or etc., as well as the quantity of the tube-contacting parts, the quantity of the tube-grasping bodies or the tube-enclosing bodies, ways of arranging them, and their location of installation.

INDUSTRIAL APPLICABILITY

The current invention relates to a tube-grasping body for grasping an insert tube in a heat exchanger, heat exchanger production methods and apparatuses utilizing the tube-grasping body, and an air conditioner and/or an outdoor unit equipped with the heat exchanger produced by the methods and apparatuses; wherein

-   -   the tube-grasping body enables the insert tube to be enlarged to         connect to a heat radiating fin for producing a heat exchanger,         still keeping the total length of insert tubes at an almost same         level comparing, even after the insert tube is enlarged by         inserting into each of through holes of heat radiating fins in         heat exchangers overlaid in their multitudes; and     -   said tube-grasping body prevents the opening of the tube and the         end-line of each of the tube-contacting parts of the         tube-grasping body, from being deformed or damaged by collision         between them, and also firmly grasps the opening side of insert         tubes sitting at the interior side in the heat exchanger, as         well as the tubes sitting at the exterior side in the heat         exchanger, in order to resolve all the problems occurring in the         following example cases: the case where the gap between insert         tubes is decreased to enable them to be inserted into a heat         radiating fin in multiple columns such as columns of 3, 4, or         etc., the case where the diameters of insert tubes being         enlarged are different according to the spec of the heat         exchanger, the case where the gap between each of straight tubes         or hairpin tubes being inserted into said heat radiating fin is         significantly decreased comparing to the prior arts, the case         where the exterior diameter of the insert tube becomes about the         same size as the interior diameter of the tube-grasping body         itself or the interior diameter between the tube-contacting         parts (the interior diameter between the bumps if bumps are         formed on the interior surface of the tube-contacting parts),         and the case where the axis of said enlargement portion is away,         by some degree, relative to the direction of the longitudinal         length of the tube-enlarging mandrel, from the axis of the         tube-grasping body.

Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. 

What is claimed is:
 1. A heat exchanger production apparatus utilizing a tube-grasping body, the apparatus wherein the tube-grasping body is used in a heat exchanger production apparatus 1; the tube-grasping body is also connectable at the exterior of a tube-enlarging mandrel 2, for moving back and forth, along said tube-enlarging mandrel 2 which is penetrable from the opening 7 b of a tube 7 inserted into a heat radiating fin 6 of a heat exchanger 5; the tube-grasping body is also equipped with a plurality of tube-contacting parts 3 f, capable of radially expanding or axially compressing in the cross direction of the longitudinal length of said tube 7; the tube-grasping body is also equipped with slopes 3 b slanting gradually in the widening direction toward the opening 7 b of the corresponding tube, wherein each of the slopes 3 b is formed on the exterior surface of each of said tube-contacting parts 3 f; the tube-grasping body is also equipped with a sliding means which radially expands or axially compresses each of said tube-contacting parts 3 f, by sliding back and forth in the longitudinal direction of the tube, along said slopes 3 b of the tube-contacting parts 3 f; a bump 3 e is formed to extrude from the interior surface of each of said tube-contacting parts 3 f, at the side of the opening 7 b, in the axial direction of the tube 7; a slope 3 m, which has a straight or curved sloping side, is formed at said bump 3 e, and slanted in the widening direction, from the summit 3 p of the bump 3 e, toward the opening 7 b of the tube 7 facing the end-line 3 o of the tube-contacting part 3 f, in order to prevent said opening 7 b from being deformed by collision of the bump 3 e with the opening 7 b of the tube 7 when the opening 7 b of the tube 7 is connected at its exterior to the tube-contacting parts 3 f; a slope 3 g, which has a straight or curved sloping side, is formed on the interior circumference of said guide-pipe 3 c at its end side, and slanted in the widening direction toward the opening 7 b of the corresponding tube 7, in order to reduce the sliding abrasion against each of the slopes 3 b formed on the exterior surface of each of said tube-contacting parts 3 f; said slope 3 b is also formed, on the exterior surface of each of the tube-contacting parts 3 f of said tube-grasping body 3, at such a position that the slope 3 b is not allowed to reach the end-line 3 o of each of said tube-contacting parts 3 f; and the tube-grasping body 3 also comprises: a configuration wherein, said tube-contacting parts 3 f, capable of radially expanding or axially compressing, are formed and separated by a plurality of slits 3 a which are of prescribed widths 3 u, and which are formed in the longitudinal direction of the tube-grasping body 3, the same direction of the movement of the tube-enlarging mandrel 2; and the width of each of said slits 3 a is gradually increased from said prescribed width 3 u to an expanded width 3 x, from a prescribed location toward the opening 7 b of said tube
 7. 2. A heat exchanger production apparatus as claimed in claim 1, the apparatus comprising: a configuration wherein, the slope 3 b is formed on the exterior surface of each of said tube-contacting parts 3 f of said tube-grasping body 3, at the rear side of the bump 3 e which is formed at the side of the opening 7 b on the interior surface of each of said tube-contacting parts 3 f, the opposite side of the end-line 3 o of the tube-contacting part 3 f, in such a way that said slope 3 b is not allowed to reach the end-line 3 o of each of the tube-contacting parts 3 f of said tube-grasping body
 3. 3. A heat exchanger production apparatus as claimed in claim 1, comprising: a configuration wherein, said tube-grasping body 3 is equipped with a tool-joining part 3 j for joining or disjoining said tube-grasping body 3, to or from the tube-grasping body holder 3 l.
 4. A heat exchanger production apparatus as claimed in claim 1, comprising: a configuration wherein, a limiting means is installed at said tube-grasping body with tube-contacting parts 3 f when said tube-grasping body 3 is held by the tube-grasping body holder 3 l, in order to limit the location of the radial expansion or the axial compression of the tube-contacting parts 3 f of the tube-grasping body
 3. 5. A heat exchanger production apparatus as claimed in claim 1, comprising: a configuration wherein, said sliding means is provided by the guide-pipe 3 c, and said guide-pipe 3 c is equipped with a tool-joining part 3 i for joining or disjoining the guide-pipe 3 c, to or from the guide-pipe holder 3 d. 